Modernize use override

[mahnen]

pull request to adress #827

[mahnen]

@KrisThielemans : Don't know if I can do something about this, one of the runners timed out while it was going well...

[KrisThielemans]

yes, that particular job is on the limit for some reason. I've committed something elsewhere that reduces the number of warnings that the compiler outputs, so possibly it'll bring it in line. So I suggest that we wait till those are merged.

Overall, this looked pretty good though. Thanks!

I think we need to follow @casperdcl 's advice, and commit the final patch with a specific author, to avoid you getting all the credit 😉 .

One thing that I'm not so sure about is the use of compile_commands.json exported by CMake. This works fine if all options are enabled and all dependencies are found. However, could it trouble otherwise ? e.g. if your system doesn't have ecat7, then CMake won't export the STIR ecat7 files, and clang-tidy will never touch them, and they could therefore become out-of-date. Of course, ideally we'd find this in CI, but unfortunately we don't test everything. (case in point: the ecat7 matrix library isn't freely available).

[KrisThielemans]

I've re-run this on current STIR in #1367, so closing this. thanks for telling me how to do this!