fix(ci): clean up broken Semantic PR

[Neudrino]

Summary

This is the first POC for the de-tanglement of the different checks. While further improvement might involve composite actions (for the Github commenting) this is seen out of scope for the first iteration.

• The semantic PR workflow is broken in so far as it has some strange interaction with the cloud-workflow. One effect was, that the semantic PR check would fail, whenever the cloud workflow would fail, even though both should be totally unrelated.
• One cause of error could be the abuse of files for the propagation of results from previous jobs. While this is speculation, a cleanup to use Github action best practices is worthwhile anyway.
• With this change the unnecessary bloat and anti-patterns in CI design are removed from the workflow.
  Output variables are totally enough for passing the status on. And this was already implemented.
• Update: Removes the unnecessary and difficult dependency on comment-pr-on-check-failure.yml.
• Update: Cleaned up the bloat of the message and only pointed to the documentation as single source of truth.

Test Plan

The workflow is

• no comment for good PR title: https://github.com/magma/magma/actions/runs/2826540979 👍
• ❌ for bad PR title: https://github.com/magma/magma/actions/runs/2826551146 👍
• ✔️ for good PR title after update: https://github.com/magma/magma/actions/runs/2826561792 👍
• no comment and skipped semantic PR check for Revert PR: https://github.com/Neudrino/magma/actions/runs/2883078711 👍

Additional Information

• This is a PR from the own repository, in order to be able to test the workflow using on: pull_request
• UNCHANGED: The notification behaviour is unchanged. I.e. there is a notification for the first (failing) post on the PR. There are no additional notifications on edited messages.

[github-actions]

Thanks for opening a PR! 💯

A couple initial guidelines

• All commits must be signed off. This is enforced by DCO check.
• All PR titles must follow the semantic commits format. This is enforced by Semantic PR.

Howto

• Reviews. The "Reviewers" listed for this PR are the Magma maintainers who will shepherd it.
• Checks. All required CI checks must pass before merge.
• Merge. Once approved and passing CI checks, use the ready2merge label to indicate the maintainers can merge your PR.

More info

Please take a moment to read through the Magma project's

• Contributing Conventions for norms around contributed code

If this is your first Magma PR, also consider reading

• Developer Onboarding for onboarding as a new Magma developer
• Development Workflow for guidance on your first pull request
• CI Checks for points of contact for failing or flaky CI checks
• GitHub-to-Slack mappings for Magma maintainers for guidance on how to contact maintainers on Slack

[github-actions]

✔️ The Semantic PR check ended with status success. See instructions on formatting your commit and pull request titles.

[nstng]

As discussed offline, please have a look at

• triggered comment-pr-on-check-failure.yml is failing iiuc
• check if the revert case is covered as in comment-pr-on-check-failure.yml
• check if edit with same text triggers a mail (i.e., check faild after rerun again)

[Neudrino]

• triggered comment-pr-on-check-failure.yml is failing iiuc

This was addressed with second commit by removing the trigger.

• check if the revert case is covered as in comment-pr-on-check-failure.yml

Yes, it is. It does behave as expected and the check and comment step will be skipped in the relevant cases.
Also added to the description.

• check if edit with same text triggers a mail (i.e., check faild after rerun again)

The behaviour is unchanged here. A notification is sent on the comment creation. There no notification on comment edit. This is Github behaviour and has nothing to do with the actual change here.

[jheidbrink]

How was the semantic PR broken? The summary says "The semantic PR workflow is broken in so far as it has some strange interaction with the cloud-workflow", but I don't know what those strange interactions are and what doesn't work.

[Neudrino]

How was the semantic PR broken? The summary says "The semantic PR workflow is broken in so far as it has some strange interaction with the cloud-workflow", but I don't know what those strange interactions are and what doesn't work.

On issue observed was, that the semantic PR check would fail, whenever the cloud workflow would fail. I.e. the semantic PR would depend on the status of the cloud workflow, even though both should be totally unrelated and independent.
(Also extended the PR description.)

[jheidbrink]

Can you link to an example where the semantic PR check failed because of the cloud workflow?

[Neudrino]

Can you link to an example where the semantic PR check failed because of the cloud workflow?

Link to some random private channel.

Some screenshots are:

(as seen in #13462)

[Neudrino]

Rebased on master to resolve conflicts from #13696.

[Neudrino]

✔️ This PR successfully de-coupled the semantic-pr and cloud-workflow. E.g. see the PR #13715 which has a broken cloud workflow, but the semantic PR is fine.
(Previously the semantic-pr would fail whenever the cloud-workflow fails.)