ci - update test suite for parity with Ratel

[zatkins-dev]

Adds make test subsearch="...", where subsearch is interpreted as a regular expression used to filter test cases by name.

Lots of people have asked for this, it wasn't too bad to add in.

Also, adds some useful output (timing, better error formatting) to TAP.

I used that output to shorten some excessively long tests (>30 s).

The parsing for arguments to TESTCASE(...) are far more robust

• quotation marks are now optional and can be escaped as \"
• there can be spaces after the commas separating arguments
• parentheses are allowed, so long as they match
• the only disallowed character is = when quotation marks aren't used, otherwise it's fine

The arguments cgns_tol, csv_rtol, and csv_ztol are now supported for per-test case tolerance settings.

[jeremylt]

note - you'll want my most recent merge to main

[zatkins-dev]

I think I just managed to catch it

[jeremylt]

Why the drop in codecov? I don't see an obvious reason

[zatkins-dev]

I really don't know...the fortran tests are definitely running