Add github action for cpp build and test

[hatemhelal]

Update CI workflow to build and test using a matrix defined by:

        compiler :
          - llvm
          - gcc

        build_type : 
          - Debug
          - Release

        simd:
          - ON
          - OFF

The build is configured to use cmake + ninja + ccache. I've tested that ccache is setup correctly on my fork.

[hatemhelal]

@asadchev let me know if you have further suggestions to check this is all working as expected. Also wonder if it makes sense to drop the Debug option from the build_type? I wondered if it made more sense to build+test on aarch64 but the number of build variants starts to grow very fast.