Improve plugin release instructions (#3591)

* Improve plugin release instructions
* Improve the improvement
* Fix broken links
* Add a link to e2e tests documentation

Signed-off-by: Carlisia <carlisia@vmware.com>

site/content/docs/main/plugin-release-instructions.md

@@ -9,9 +9,22 @@ Container images are built via a CI job on git push.
 
 Plugins the Velero core team is responsible include all those listed in [the Velero-supported providers list](supported-providers.md) _except_ the vSphere plugin.
 
+
+## Steps
+### Open a PR to prepare the repo
 1. Update the README.md file to update the compatibility matrix and `velero install` instructions with the expected version number and open a PR.
-  1. Determining the version number is based on semantic versioning and whether the plugin uses any newly introduced, changed, or removed methods or variables from Velero.
-1. Once the updated README.md PR is merged, checkout the upstream `main` branch. `git checkout upstream/main`.
+1. Determining the version number is based on semantic versioning and whether the plugin uses any newly introduced, changed, or removed methods or variables from Velero.
+2. Roll all unreleased changelogs into a new `CHANGELOG-v<version>.md` file and delete the content of the `unreleased` folder. Edit the new changelog file as needed.
+### Tag
+1. Once the PR is merged, checkout the upstream `main` branch. Your local upstream might be named `upstream` or `origin`, so use this command: `git checkout <upstream-name>/main`.
 1. Tag the git version - `git tag v<version>`.
-1. Push the git tag - `git push --tags <upstream remote name>`
-1. Wait for the container images to build
+1. Push the git tag - `git push --tags <upstream-name>` to trigger the image build.
+2. Wait for the container images to build. You may check the progress of the GH action that triggers the image build at `https://github.com/vmware-tanzu/<plugin-name>/actions`
+3. Verify that an image with the new tag is available at `https://hub.docker.com/repository/docker/velero/<plugin-name>/`.
+4. Run the Velero [e2e tests][2] using the new image. Until it is made configurable, you will have to edit the [plugin version][1] in the test.
+### Release
+1. If all e2e tests pass, go to the GitHub release page of the plugin (`https://github.com/vmware-tanzu/<plugin-name>/releases`) and manually create a release for the new tag. 
+1. Copy and paste the content of the new changelog file into the release description field.
+
+[1]: https://github.com/vmware-tanzu/velero/blob/c8dfd648bbe85db0184ea53296de4220895497e6/test/e2e/velero_utils.go#L27
+[2]: https://github.com/vmware-tanzu/velero/tree/main/test/e2e

site/content/docs/main/release-instructions.md

@@ -98,7 +98,7 @@ These are the steps to update the Velero Homebrew version.
 - Run `hack/release-tools/brew-update.sh`. This script will download the necessary files, do the checks, and invoke the brew helper to submit the PR, which will open in your browser.
 - Update Windows Chocolatey version. From a Windows computer, follow the step-by-step instructions to [create the Windows Chocolatey package for Velero CLI](https://github.com/adamrushuk/velero-choco/blob/main/README.md)
 -
-### Plugins
+## Plugins
 
 To release plugins maintained by the Velero team, follow the [plugin release instructions](plugin-release-instructions.md).
 
@@ -132,4 +132,4 @@ What to include:
 
 [1]: https://velero.io/blog
 [2]: website-guidelines.md
-[3]: test/e2e/velero_utils.go
+[3]: https://github.com/vmware-tanzu/velero/tree/main/test/e2e

site/content/docs/v1.6/plugin-release-instructions.md

@@ -9,9 +9,22 @@ Container images are built via a CI job on git push.
 
 Plugins the Velero core team is responsible include all those listed in [the Velero-supported providers list](supported-providers.md) _except_ the vSphere plugin.
 
+
+## Steps
+### Open a PR to prepare the repo
 1. Update the README.md file to update the compatibility matrix and `velero install` instructions with the expected version number and open a PR.
-  1. Determining the version number is based on semantic versioning and whether the plugin uses any newly introduced, changed, or removed methods or variables from Velero.
-1. Once the updated README.md PR is merged, checkout the upstream `main` branch. `git checkout upstream/main`.
+1. Determining the version number is based on semantic versioning and whether the plugin uses any newly introduced, changed, or removed methods or variables from Velero.
+2. Roll all unreleased changelogs into a new `CHANGELOG-v<version>.md` file and delete the content of the `unreleased` folder. Edit the new changelog file as needed.
+### Tag
+1. Once the PR is merged, checkout the upstream `main` branch. Your local upstream might be named `upstream` or `origin`, so use this command: `git checkout <upstream-name>/main`.
 1. Tag the git version - `git tag v<version>`.
-1. Push the git tag - `git push --tags <upstream remote name>`
-1. Wait for the container images to build
+1. Push the git tag - `git push --tags <upstream-name>` to trigger the image build.
+2. Wait for the container images to build. You may check the progress of the GH action that triggers the image build at `https://github.com/vmware-tanzu/<plugin-name>/actions`
+3. Verify that an image with the new tag is available at `https://hub.docker.com/repository/docker/velero/<plugin-name>/`.
+4. Run the Velero [e2e tests][2] using the new image. Until it is made configurable, you will have to edit the [plugin version][1] in the test.
+### Release
+1. If all e2e tests pass, go to the GitHub release page of the plugin (`https://github.com/vmware-tanzu/<plugin-name>/releases`) and manually create a release for the new tag. 
+1. Copy and paste the content of the new changelog file into the release description field.
+
+[1]: https://github.com/vmware-tanzu/velero/blob/c8dfd648bbe85db0184ea53296de4220895497e6/test/e2e/velero_utils.go#L27
+[2]: https://github.com/vmware-tanzu/velero/tree/main/test/e2e

site/content/docs/v1.6/release-instructions.md

@@ -98,7 +98,7 @@ These are the steps to update the Velero Homebrew version.
 - Run `hack/release-tools/brew-update.sh`. This script will download the necessary files, do the checks, and invoke the brew helper to submit the PR, which will open in your browser.
 - Update Windows Chocolatey version. From a Windows computer, follow the step-by-step instructions to [create the Windows Chocolatey package for Velero CLI](https://github.com/adamrushuk/velero-choco/blob/main/README.md)
 -
-### Plugins
+## Plugins
 
 To release plugins maintained by the Velero team, follow the [plugin release instructions](plugin-release-instructions.md).
 
@@ -132,4 +132,4 @@ What to include:
 
 [1]: https://velero.io/blog
 [2]: website-guidelines.md
-[3]: test/e2e/velero_utils.go
+[3]: https://github.com/vmware-tanzu/velero/tree/main/test/e2e