Improve CI and fix tests

[christophfroehlich]

Build also the tests on the non-cmake CI jobs.

Needs some changes to successfully build on windows, and the test on RHEL8 with a different fmt version:

    /__w/RSL/RSL/src/PickNikRobotics/RSL/tests/parameter_validators.cpp:347: FAILED:
      CHECK( result.error() == "Parameter 'test' with the value '0' is not in the set '{1, 2, 3.5}'" )
    with expansion:
      "Parameter 'test' with the value '0.0' is not in the set '{1.0, 2.0, 3.5}'"
      ==
      "Parameter 'test' with the value '0' is not in the set '{1, 2, 3.5}'"

[otamachan]

I tested the same changes on my fork (otamachan#1) and all CI passed, including Windows and RHEL.

The stringify helper with {:g} is a reasonable approach for the fmt output inconsistency across platforms.