combined code coverage

[nerohmot]

CD should not run the tests anymore, but CD mus wait that CI is finished.
CI needs 3 parts:

• Linux
• MacOS (needs adding)
• Windows

each of these jobs need to wait for the previous to finish, and APPEND their codecoverage to the previous one.

... upload ?!?

then CD should ... download ?!? and push the COMBINED code coverage to codecov.