Check Python and C++ formatting in the CI
Taking the CI configuration from LHCb@65edd2e8.
From what I can tell, the formatting script only checks files that have changed with respect to master. Because I don't touch any of the files in this MR, the CI passes, even though our Python files don't conform to the style.
We can touch the files in a separate commit to get trigger the formatting, but this needs coordination with the other open MRs.
Closes #23 (closed).
Edited by Alex Pearce