While we might never be able to have 100% of our code strict, we can at
the very least do it for all of our tests. This ensures that our tests
are using our API with the types as intended by the test author, and not
silently be cast to what our API requires.
PR #3513, developed by @SaidkhojaIftikhor, has been stuck for some time awaiting tests. This is the first of three PRs to replace that one. This accomodates the use of slash as a delimiter in functions TEXTAFTER, TEXTBEFORE, TEXTSPLIT, and NUMBERVALUE. The source changes are very simple. Additional tests exercise all the source changes.