357 plan UUID parameter

[Rikuoja]

Turns out #357 was already there, but it wasn't tested.

So here is just a bunch of tests verifying that if only one plan is specified, then only one plan is processed.

[github-actions]

The backport to vsl failed:

The process '/usr/bin/git' failed with exit code 128

stderr

remote: Permission to GispoCoding/hame-ryhti.git denied to github-actions[bot].
fatal: unable to access 'https://github.com/GispoCoding/hame-ryhti.git/': The requested URL returned error: 403

To backport manually, run these commands in your terminal:

# Fetch latest updates from GitHub
git fetch
# Create a new working tree
git worktree add .worktrees/backport-vsl vsl
# Navigate to the new working tree
cd .worktrees/backport-vsl
# Create a new branch
git switch --create backport-367-to-vsl
# Cherry-pick the merged commit of this pull request and resolve the conflicts
git cherry-pick 9ccc1cbef440e4c0c7ba6ed9c04dae8cdc0f8387,4b205fbaa10777172d4b8de38dde7598cc0d2e53
# Push it to GitHub
git push --set-upstream origin backport-367-to-vsl
# Go back to the original working tree
cd ../..
# Delete the working tree
git worktree remove .worktrees/backport-vsl

Then, create a pull request where the base branch is vsl and the compare/head branch is backport-367-to-vsl.

[LKajan]

Manually backported in #369