easyblock PR patches never applied when running in dry run mode

[ocaisa]

I noticed in easybuilders/easybuild-easyblocks#2726 (comment) that PR patches are never actually applied when running in extended dry run mode. This is probably a bit unexpected, forcing you to run the installation to see the impact of any changes.

[ocaisa]

Now that I think about it, this most only be true for easyblock PRs, you can definitely use -D and -M with easyconfig PRs.

[boegel]

This probably means we're not forcing an apply_patch call when running in dry run mode, probably the one in fetch_files_from_pr?