Duplicated test logic

[travitch]

There is a bit of logic duplicated in the architecture backend tests that saves macaw IR for debugging purposes e.g.,:

macaw/macaw-ppc/tests/PPCTests.hs

Lines 45 to 49 in f217bf8

	instance TTO.IsOption SaveMacaw where
	defaultValue = SaveMacaw False
	parseValue v = SaveMacaw <$> TTO.safeReadBool v
	optionName = pure "save-macaw"
	optionHelp = pure "Save Macaw IR for each test case to /tmp for debugging"

We should consolidate this into one place. The major question is where. We could put it in a new module like Data.Macaw.Testing in macaw-base, or split out this common testing functionality into a new package like macaw-testing.

[RyanGlScott]

There is some prior art in macaw-symbolic's Data.Macaw.Symbolic.Testing module, so it wouldn't be too much of a stretch to put Data.Macaw.Testing in macaw-base. We could also split out the testing logic into their own packages, although we'd likely need both macaw-testing and macaw-testing-symbolic.

[travitch]

I did that out of expedience, but I'm not sure that I like having a dependency on a testing library in one of the core libraries. That generally doesn't feel great, and I've been burned by weird e.g., quickcheck dependency issues before. I'm not opposed obviously, but maybe a general macaw-testing library to hold all of that might be better