build(deps-dev): Bump watchpack from 2.3.0 to 2.3.1 in /docs (#7430)

Bumps [watchpack](https://github.com/webpack/watchpack) from 2.3.0 to 2.3.1.
- [Release notes](https://github.com/webpack/watchpack/releases)
- [Commits](https://github.com/webpack/watchpack/compare/v2.3.0...v2.3.1)

---
updated-dependencies:
- dependency-name: watchpack
  dependency-type: direct:development
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>
Co-authored-by: Sam Kleinman <garen@tychoish.com>
Co-authored-by: M. J. Fromberger <fromberger@interchain.io>

docs/package.json

@@ -7,7 +7,7 @@
     "vuepress-theme-cosmos": "^1.0.182"
   },
   "devDependencies": {
-    "watchpack": "^2.3.0"
+    "watchpack": "^2.3.1"
   },
   "scripts": {
     "preserve": "./pre.sh",