Fix https://github.com/scylladb/scylla-docs/issues/4125
I've added the upgrade guides from 5.0 to 2022.1. They are based on the previous upgrade guides from Open Source to Enterprise.
Closes#11108
* github.com:scylladb/scylladb:
doc: apply feedback about scylla-enterprise-machine-image
doc: update the note about installing scylla-enterprise-machine-image
update the info about installing scylla-enterprise-machine-image during upgrade
doc: add the requirement to install scylla-enterprise-machine-image if the previous version was installed with an image
doc: update the info about metrics in 2022.1 compared to 5.0
doc: minor formatting and language fixes
doc: add the new guide to the toctree
doc: add the upgrade guide from 5.0 to 2022.1