Don't trigger full build+test CI when only markdown files are edited

[kitsiosk]

Description

Change Summary

Currently, the build CI workflow will run even when a push changes only markdown files (e.g., README.md).
With these changes, a push that changes only markdown files will not trigger the workflow, thus speeding up the project's CI and saving compute resources 🌱 (see below for quantity).

Example

Here is an example of the behaviour described above: the commit 306833f changed these files: CHANGELOG.md and, when pushed, triggered this workflow run, which ran for ~1.5 CPU hours. With the proposed changes, these 1.5 CPU hours would have been saved, clearing the queue for other workflows and speeding up the CI of the project, while also saving resources in general 🌱.

Note that this is a single example out of (a minimum of) 81 examples over the last few months; a lower estimate for the accumulated gain is 23 CPU hours, but the actual number could be much higher because we could only look at a subset of the data.

Other such examples include 42213cc, b99b248, 17b287c.

Context

Hi,

We are a team of researchers from University of Zurich and we are currently working on energy optimizations in GitHub Actions workflows.

Thanks for your time on this.

Kindly let us know (here or in the email below) if you would like to **ignore other file types **or apply the filter to other workflows, or if you have any question whatsoever.

Best regards,
Konstantinos Kitsios
[email protected]

Checklist:

• Tests added/updated.
• Documentation updated. Documentation is generated from docstrings - these must be updated according to your change.
  If a new method has been added it should be referenced in cognite.rst in order to generate docs based on its docstring.
• Changelog updated in CHANGELOG.md.
• Version bumped. If triggering a new release is desired, bump the version number in _version.py and pyproject.toml per semantic versioning.

[kitsiosk]

Converted to draft because I realized that you have branch protection rules that require the workflow to pass in order for a PR to be merged. Apparently, Github does not consider skipped workflows as passes, which is weird as noted by many others: https://github.com/orgs/community/discussions/44490

I will see if there is something we can do in this case, otherwise I will close this one.