Enable immutable releases

[ericcornelissen]

This action should enable immutable releases to help protect users against potential attacks such as GHSA-mrrh-fwg8-r2c3 by preventing re-pointing (released) tags to different commits.

[tim-hanssen]

Yes @ericcornelissen is right, I think immutable releases are becoming quickly much more important GHSA-69fq-xp46-6x23