Add option to silence warning for skip/skip_if

[tom91136]

Hello, Bristol site here 😀

We have a fairly large parameter space that tries to compile and run a benchmark (i.e BabelStream, with programming model and compiler as parameters). Right now we have about 10% of the cases being skipped, is there a less severe logging level that conveys the skipped tests are by design and intended? In our case the parameter packs are not flexible enough because the tests are generated from a custom spec YAML file similar to the ones in the tutorial.