This MR renovates the CI by
- updating to the latest SFT LCG release allpix-squared/allpix-squared!378 (merged)
- cleaning up the YML definition
- moving to a Direct Acyclic Graph running of the pipeline allpix-squared/allpix-squared!368 (merged)
- adding code that exposes testing results to GitLab allpix-squared/allpix-squared!399 (merged)
- updates the way, Clang Format and Clang Tidy are found and used
All these changes are ported from the Allpix Squared repository.