inject-checksums does not work for bundle components

[mboisson]

When working on PR easybuilders/easybuild-easyconfigs#11113 I wanted to use --inject-checksums to add them for the bundle components. This did not work. If checksums were absent, nothing was added. If checksums were present, they would be detected and EB would complain about that, but when using --force, they would not get over-written.

[akesandgren]

This is annoying, we should try to fix this...

[boegel]

I agree. The problem is that strictly speaking framework doesn't know about specific easyblocks like Bundle (and components is an easyblock-specific eaysconfig parameter).

So the logic to inject checksums for bundle components should be implemented in the Bundle easyblock itself, in a dedicated method, and framework should call out to that method when it's injecting checksums...