Re #7215. Change testing strategy to avoid occasional failures.

I think the sporadic failures of this test were because alg2 had not
started up even after the sleep. Calling validateInputs() instead
accomplishes the same testing goal and avoid having to execute this
instance of the algorithm at all.
Re #7215. Use the same simplification in other places.

I don't think I've seen these tests fail, but this is a simpler way
to test the same thing so use it here as well.
Re #7215. Fix some tests that had unprotected constructors.

Not related to this ticket, just sneaked it in here when I noticed it.
Re #7215. Minor simplification.
Merge branch 'feature/7218_monitorlivedata_occasional_test_failures' into develop