[feat(ci)]: Don't run all the CI (e.g. node tests, happo) for documenation changes

[brandonlenz]

Describe the solution you'd like

Node tests only run when relevant files change (e.g. CI files or src files)

all-contributors or other documenation-only PRs should not be required to wait on full test runs and happo diffs, etc

Describe alternatives you've considered

Leave it the way it is, but for small non-code PRs it introduces slower than desired feedback loop

[brandonlenz]

Did some looking in to this, and there are some frustrating limitations with GitHub Actions that make solving this a matter of composing workarounds.

Right now, we want to enforce that certain CI checks run in order to merge to main.

If we use github's native path filtering, the checks don't run for documentation, release, or all-contributors PRs, preventing us from being able to merge them normally.

Since we're an open source repo, it won't accrue cost to us, but a workaround is to introduce conditional steps within a workflow so that we simply skip steps based on files changed in each workflow. Skipped steps still count as a workflow not failing, so would not block PRs. These would count as 1 action minute even if they only execute for 1ms. Again, not a cost issue since our repo is open source.

It would add some visual complexity/clutter to our existing workflows, but is doable.

[brandonlenz]

duplicate of #2376