Scrutinizer had previously suggested annotations for 3 LookupRef tests, but it no longer accepts its own annotation for those cases. This PR cleans them up. ColumnsTest and RowsTest are extremely straightforward.
IndexTest is a bit more complicated, but only because, unlike the other two, it had no test which executed in the context of a spreadsheet. And, when I added those, I discovered a couple of bugs. INDEX always requires at least 2 parameters (row# is always required), but its entry in the function table specified 1-4 parameters, now changed to 2-4. And, omitting col# is not handled the same way as specifying 0 for col#, though the code had treated them identically. (The same would have been true for row# but, because it is now required, ...)
d27b6a672a