Better testing

[TomerFi]

What did you have in mind?

We need better testing of the shell script in CI workflows,
today - we basically just test the build and deploy process of the image,
any errors in the underlying shell script might go undetected.

The best "test" we have for the shell script now is the fact we dogfood it for the release workflow,
so technically if the shell script breaks, we won't be able to release.
Nevertheless, more thorough tests for pull requests will be much better.

Are you trying to fix a problem?

Catch bugs and errors early.

Any lead on how this feature may be implemented?

Inspiration might come from version-bumper-action's CI workflows,
a GitHub action that uses this image and performs better tests for pull requests and staging.

[welcome]

Thanks for opening your first issue here!