Post comment for PRs from forks

[lukastaegert]

This PR contains:

• bugfix
• feature
• refactor
• documentation
• other

Are tests included?

• yes (bugfixes and features will not be merged without tests)
• no

Breaking Changes?

• yes (breaking changes will not be merged unless absolutely necessary)
• no

List any relevant issue numbers:

Description

This will post a "thank you" comment with testing instructions to PRs from forks. It will not auto-update the REPL link because that is kind of tricky, but at least people see how they can try out stuff in theory.

[codecov]

Codecov Report

Merging #4027 (c3b5795) into master (c008f3e) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #4027   +/-   ##
=======================================
  Coverage   97.47%   97.47%           
=======================================
  Files         192      192           
  Lines        6771     6771           
  Branches     1983     1983           
=======================================
  Hits         6600     6600           
  Misses         84       84           
  Partials       87       87           

---

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[github-actions]

Thank you for your contribution! ❤️

You can try out this pull request locally by installing Rollup via

npm install rollup/rollup#move-to-github-actions

or load it into the REPL:
https://rollupjs.org/repl/?circleci=14851