chore: format Jenkinsfile

[lemeurherveCB]

This PR formats the Jenkinsfile pipeline as there were some bad indentations and a mix of tabs and spaces rendering the indentation unreadable in VS Code.
It also uses single quotes where double quotes aren't needed.

It finally adds a .git-blame-ignore-revs file so GitHub could ignores the format commit in the blame view:

• Doc: https://docs.github.com/en/repositories/working-with-files/using-files/viewing-and-understanding-files#ignore-commits-in-the-blame-view (can be bypassed)
• Corresponding blame view: https://github.com/jenkinsci/docker/blame/cd4c45957ab3a9e0134f3431813c1e58f2913d11/Jenkinsfile
• Corresponding blame view bypassing this: https://github.com/jenkinsci/docker/blame/cd4c45957ab3a9e0134f3431813c1e58f2913d11~/Jenkinsfile

Tip

Review with whitespace hidden: https://github.com/jenkinsci/docker/pull/2003/files?diff=unified&w=1

Extracted from:

• chore: use TOML config with buildx to avoid DockerHub rate limits #2002

Testing done

CI (no code change)

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[timja]

you would normally add this in a follow up, if this PR gets squashed or rebase merged it won't be this value

[lemeurherveCB]

Good point. Please don't squash? 😅