Use path filter for GH actions

[philipphofmann]

Description

When opening #2784, which only touches the PR request template, I noticed that GH actions run almost all checks, which is unnecessary.

We can use path filters for some of the workflows like buildandtest.yml or e2e.yml to avoid unneeded GH action runs.

You can have a look at Cocoa 1, Cocoa 2 for reference

[github-actions]

This issue has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[krystofwoldrich]

• Implemented in Ref: Skip CI for commits without code changes #3545