Web: Don't run e2e and unit tests on ready-release-go PR

[kulmann]

Would be great if we could skip the e2e and unit test pipelines on the release PRs that get created by the ready-release-go plugin. The PRs only create changelog content.

Naive idea for web: could we skip e2e and unit test pipelines when there were only changes in .md files? Or some other reliable check that code, dependencies and build environment weren't changed?

Motivation: ready-release-go runs each and every time a PR gets merged, which means: even in best case one PR runs the CI with all the compute it binds at least twice. Hope we can improve this.

TODO:

• Web : [tests-only] skip unit and e2e test pipelines on ready-release-go prs web#1714
  [tests-only] correct release PR condition to use build.sender web#1736
• Opencloud [tests-only] Skip test related pipelines for ready-release-go PRs opencloud#2011
• Reva test(ci): skip pipelines for ready-release-go PRs reva#456
• Desktop test(ci): skip test related pipelines for ready-release-go PRs desktop#756

[saw-jan]

Let's implement this for other repos as well.
Repos:

• opencloud
• desktop
• reva

[prashant-gurung899]

Closing this issue as the test-skipping logic for release PRs has now been implemented across all repositories.

CC @saw-jan @individual-it @kulmann