contrib: Skip RPM scriptlets during cleanup

[ckyrouac]

This cleanup removes packages from the previous OS in a special root context. Their erase scriptlets can fail or act on the wrong system, so skip them.

Fixes #2559

[jeckersb]

re: my comment over in #2560 (comment) I think I was wrong about alternatives getting "outside" of the --/root=sysroot because rpm is running the scriptlets inside of a chroot. But I think something goofy still happens when you kill the entire system like that in one transaction. I'm trying to poke a bit more in testing-farm just to better understand.

I think this is probably still the correct fix, though, regardless of the outcome of my investigation.

[jeckersb]

Ok more added in #2559 (comment), I'm less certain about this approach now. This PR would probably be sufficient, but given the added context feels a bit hacky.

[cgwalters]

I'm not a fan of skipping all scripts; it's a big hammer. Not saying it's wrong but a targeted fix feels better.

[ckyrouac]

The goal of the bootc-destructive-cleanup-script is to reduce disk space used by the old system without removing interesting configs/user defined state. Seems like it'd be best to ensure the RPMs are removed since that will most likely be the largest chunk of disk space to free. Although I'm not sure what is typically done in a post uninstall script, so maybe there is some significant space that would be freed that we would miss when using --noscripts.