Checking coding convention in CI

[intjftw]

Currently there is only one job in the GitHub workflow that is responsible for building and testing CC. There should be another job that is runs a coding convention check on the code, and shows discrepancies.

This job should run in parallel with the building and parsing job without impeding this job. It should check C++, JavaScript, Java, and C# code. E.g. for C++, clang-format could do the work well.