GitHub CI checks every pull request, even those which only modify .md files.

[toboil-features]

I see it wasteful at the side of GitHub CI to compile for all the architectures exact the same binaries, which haven't been modified.
I, from time to time, do changes in .md files and see no sense in it. Even encountering Markdown validator, it should not be running on 7 different architectures just to check if wiki file is correct.

[danbev]

You can add [no ci] to pull requests commit messages to avoid running CI checks. We should add path filtering to avoid this but until then skipping ci can be used.