Job summaries/commit comments treat markdown line breaks as hard breaks but they should be soft

[jsoref]

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Bug

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This is a recurring problem, GitHub isn't consistent in how it handles soft breaks in Markdown.

Here's the sample input:

https://github.com/check-spelling/spell-check-this/blob/979517e0940820ee1353cd937b27c9b31f021dc5/.github/actions/spelling/advice.md

I've inlined the markdown between --- and ---:

---

If the flagged items are 🤯 false positives

If items relate to a ...

• binary file (or some other file you wouldn't want to check at all).

  Please add a file path to the excludes.txt file matching the containing file.

  File paths are Perl 5 Regular Expressions - you can test yours before committing to verify it will match your files.

  ^ refers to the file's path from the root of the repository, so ^README\.md$ would exclude README.md (on whichever branch you're using).

• well-formed pattern.

  If you can write a pattern that would match it,
  try adding it to the patterns.txt file.

  Patterns are Perl 5 Regular Expressions - you can test yours before committing to verify it will match your lines.

  Note that patterns can't match multiline strings.

🚂 If you're seeing this message and your PR is from a branch that doesn't have check-spelling,
please merge to your PR's base branch to get the version configured for your repository.

---

Rendered in GitHub, can appear like:

or

Rendered in preview in GitHub discussions, it appears as:

or

Rendered in an Action: https://github.com/check-spelling/jenv/actions/runs/5213088572#summary-14111202800

or

Rendered as a comment on a commit:
check-spelling-sandbox/jenv@865633a#commitcomment-117268583

or

This seems like a similar request to #21065