feat(snapshot workflow): Allow snapshots from bugfix branches

[rafaelmag110]

WHAT

This PR proposes a refactor to the determine-version job of the publish-new-snapshot workflow, that improves the job to resolve the correct snapshot version string from the gradle.properties every time. This version string is then used as input for the various publishing workflows.

As the publish-new-snapshot workflow can be manually activated, this improvement also allows for the creation of a snapshot from any branch.

WHY

To allow snapshots from bugfix branches.

FURTHER NOTES

In light of #1543, also took the opportunity to remove some unnecessary "listeners" from the run-all-tests workflow, making the file simpler.

• Removed any reference to the releases branch as its not needed anymore.
• Removed any reference to previews/* branches as they are not needed anymore.
• Checking if the github.event_name == pull_request is redundant, since that event can't trigger the workflow.
• We don't need to run all tests on tag push or release publication, since the tests were already executed a) on PR and b) on the branch from where the tag/release will be pushed/published.

Closes #1557

[sonarqubecloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
0.0% Coverage on New Code
0.0% Duplication on New Code

See analysis details on SonarCloud

[rafaelmag110]

@paullatzelsperger @wolf4ood @ndr-brt