fix: Fix 'Changes' actions of the Source Control panel

[RomanNikitenko]

What does this PR do?

Backport of #502

What issues does this PR fix?

eclipse-che/che#23323

How to test this PR?

• Go to the dashboard => Create Workspace page
• put quay.io/che-incubator-pull-requests/che-code:pr-501-amd64 to the Editor image field and select any sample
• open a file, provide any change
• open Source Control panel => ... => More actions => Changes submenu
• Check if actions of Changes submenu are enabled
• Try to use any action from that submenu

Does this PR contain changes that override default upstream Code-OSS behavior?

• the PR contains changes in the code folder (you can skip it if your changes are placed in a che extension )
• the corresponding items were added to the CHANGELOG.md file
• rules for automatic git rebase were added to the .rebase folder

[github-actions]

Click here to review and test in web IDE:

[github-actions]

Pull Request images published ✨

Editor: quay.io/che-incubator-pull-requests/che-code:pr-501-amd64
Dev image: quay.io/che-incubator-pull-requests/che-code-dev:pr-501-dev-amd64

[devspacesbuild]

Build 3.19 :: code_3.19/2: Console, Changes, Git Data

[devspacesbuild]

Build 3.19 :: sync-to-downstream_3.19/17: Console, Changes, Git Data

[devspacesbuild]

Build 3.19 :: get-sources-rhpkg-container-build_3.19/19: Console, Changes, Git Data