Change release CI to only build on tag

[BastiaanOlij]

This changes the release steps in our github action to only build when tagged (i.e. we manually create a release) instead of whenever something is merged into master. This way we can properly structure alpha and beta releases.
These changes also prevent the release info from being overwritten.

[vilhalmer]

This does make it even harder to test CI changes, is there some established pattern for GitHub Actions to build for PRs that change the action config itself?

[beniwtv]

I think originally I set it this way as we were getting requests for kind of "nightly" builds that people could test. However, this was also during times when this plugin was still under heavy development.

[vilhalmer]

I'm not personally using the CI-generated builds for anything, so I don't mind either way.

[BastiaanOlij]

This does make it even harder to test CI changes, is there some established pattern for GitHub Actions to build for PRs that change the action config itself?

The artifacts are still uploaded to the actions run for each PR. So if you go to the checks tab and then click on the "build to push", you'll find them for download there. I need to look into this a little closer because it should be possible to even make them downloadable from the checks tab itself, that's definitely how things are setup for the main Godot repo.

I think originally I set it this way as we were getting requests for kind of "nightly" builds that people could test. However, this was also during times when this plugin was still under heavy development.

That's what I followed for awhile as well, but it just fills the releases page with so much history, it's impossible to find real pre-releases.