Set up formatting CI runner

Our extant GitLab CI config runs clang-format and yapf only for merges into the master branch.

We would like to ensure merges into spiir-O4-EW-development maintain our formatting standards.

We may not be able to run this on the ligo GitLab runners.

Investigate and set up a runner for formatting.

Note: After this is complete will will likely have to do another mass formatting update to correct for any formatting errors that have been merged since !23 (merged) and !24 (merged).