Use a different changelog generator

[juraj-hrivnak]

The current changelog generator seems to generate a changelog only from issues. And unfortunately, that does not help that much. I suggest using the TheRandomLabs/ChangelogGenerator that is specially designed for Minecraft modpacks.

[froehlichA]

I was previously using metcalfc/changelog-generator, but that generator breaks if it is executed with no releases published, which is why I have to use the current one.

Best case scenario would be a changelog generator like you mentioned built into a github action,
otherwise I'll take a look at other available options.