Allow empty line after block open before a comment or compound statement

[henriholopainen]

Description

I tried to follow the discussion around empty lines after a block open from issue #3551. From what I gathered from the different issues linked to this, is that Black won't go back to allowing the empty line at block open, but loosening this rule a bit might be beneficial for some users. This PR enables empty lines after a block open for comments (# comments or """comments""") and compound statements, as suggested by @JelleZijlstra. I understand that this is a complicated topic and this change might not be accepted in the end, but just wanted to put this out there, as it seemed like a low-hanging fruit.

Checklist - did you ...

• Add an entry in CHANGES.md if necessary?
• Add / update tests if necessary?
• Add new / update outdated documentation?

[github-actions]

diff-shades results comparing this PR (ebd9677) to main (0a37888). The full diff is available in the logs under the "Generate HTML diff report" step.

╭─────────────────────── Summary ────────────────────────╮
│ 2 projects & 2 files changed / 3 changes [+3/-0]       │
│                                                        │
│ ... out of 2 500 866 lines, 11 760 files & 23 projects │
╰────────────────────────────────────────────────────────╯

Differences found.

What is this? | Workflow run | diff-shades documentation

[JelleZijlstra]

Thank you!

[henriholopainen]

How should the issue be handled? I can't close it, but do you want to keep it open still?