add sanitycheck_dependencies easyconfig parameter

[Crivella]

Allow having a separate set of dependencies loaded only at sanity check.

NOTE:

Thinking about this more, this might not be as straight-forward, as I think the idea of sanity-checking is to test whether all commands work properly with only the build module loaded.

Introducing extra modules could make a check pass that supposedly should not...

[boegel]

Using this would indeed sort of defeat the purpose of the sanity check, but I can imagine there are cases where it would make sense, for example if you want to use an extra command in a sanity check command that is not available by default, but which is not required to use the software in the normal way.

@Crivella What use case did you have for this exactly?

[Crivella]

This starting idea for this was easybuilders/easybuild-easyconfigs#22930 where I wanted to use pkg-config to check that the patch we apply to the .pc files to add libtiff as a required dependency actually does not break the command.

Still i think for this to be robust we would need not only sanity_check_deps but also a separate sets of commands that are supposed to be ran with these extra dependencies loaded, so that all the other sanity checks can be still performed in the normal way