Standardise convention around references to "QC check"/"QC test" etc.

[intarga]

QC checks are sometimes referred to as checks, sometimes as tests, sometimes with the "QC" prefix, sometimes not. We should really come up with a convention and stick to it.

I favour going for "checks", because "tests" leads to a lot of confusion with unit/integration tests, and the "QC" prefix was introduced to mitigate this confusion, so is superfluous if we stop using "tests"