Modify r2.2 release plan from public back to release-candidate - #114

What type of PR is this?

Add one of the following kinds:

• subproject management

What this PR does / why we need it:

As mentioned in #112

r4.2 is the second release candidate of Commonalities, therefore it can't already yet be used to create a public release for Spring26. Please change the release-plan.yaml in the meantime back to rc. You can create a second release candidate release to get a review and be sure that everything fits for the later public release (when Commonalities r4.3 is available).

Modify r2.2 release plan from public back to release-candidate

Which issue(s) this PR fixes:

Fixes #

Special notes for reviewers:

Changelog input

 release-note