Adds CI check for clang-tidy.

[christianparpart]

add CI check for clang-tidy.

[whisperity]

This is already performed by the CodeChecker job. It calls Tidy. And newer versions will also be able to call CppCheck!

[whisperity]

Also we can set the CI job to run Clang-Tidy in a way that it respects the .clang_tidy files. I don't remember the flag for this at the tip of my tongue but can look it up!

[christianparpart]

This is already performed by the CodeChecker job. It calls Tidy. And newer versions will also be able to call CppCheck!

yeah, I'm mostly interested in enforcing a proper coding style. I'm not sure why clang-format is not doing that for the identifier naming conventions. IMHO that would be fitting there, too, but yeah...

[christianparpart]

Also we can set the CI job to run Clang-Tidy in a way that it respects the .clang_tidy files. I don't remember the flag for this at the tip of my tongue but can look it up!

this would be generally a nice idea nevertheless. but with this PR, i kinda failed. I didn't find the right action to do what I want. I didn't think it would be THAT hard.
The actions I found (so far), utilizing clang-tidy, have been all way too hard-coded and very inflexible. And the current one used in this PR actually fails because it's running cmake within a docker container, and hence is missing all the dependencies for a proper run (lol).