bump-formula-pr: add release notes if found

[SMillerDev]

• Have you followed the guidelines in our Contributing document?
• Have you checked to ensure there aren't other open Pull Requests for the same change?
• Have you added an explanation of what your changes do and why you'd like us to include them?
• Have you written new tests for your changes? Here's an example.
• Have you successfully run brew style with your changes locally?
• Have you successfully run brew typecheck with your changes locally?
• Have you successfully run brew tests with your changes locally?

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This should allow maintainers to quickly spot important information about a release (if it's on GitHub)

[BrewTestBot]

Review period will end on 2023-03-08 at 18:42:51 UTC.

[BrewTestBot]

Review period skipped due to critical label.

[RandomDSdevel]

     I could be wrong, but I just thought I'd note thatthis change feels like it's doing a bit of work in roughly the same space as the old #2935 and #5744, albeit not as a user-facing 'brew' command, internal or external, and only covering formulas and casks from GitHub with release notes extractable from GitHub Releases pages.

[SMillerDev]

Yeah, I had a similar idea to those but toned it down to this to start with.

[chenrui333]

Like the idea, but we might need to find a way of replacing all the github issue links in the release notes, currently, it messed up the PR/issue references in homebrew-core repo.

[MikeMcQuaid]

Like the idea, but we might need to find a way of replacing all the github issue links in the release notes, currently, it messed up the PR/issue references in homebrew-core repo.

@chenrui333 Can you provide some examples? Thanks!

[SMillerDev]

Someone can wrap it in <pre></pre> but I don't have time for that now.