The error message rendered from the `UndefinedMacroException` when
raised by a TestBuilder is very vague as to where the problem is
and how to resolve it. This commit adds a basic amount of
information about the specific model and column that is
referencing an undefined macro.

Note: All custom macros referenced in a generic test config will
raise an UndefinedMacroException as of v0.20.0.

I realized that this exception information would be better if
CompilationExceptions inclulded the file that raised the exception.
To that end, I created a new exception handler in `_parse_generic_test`
to report on CompilationExceptions raised during the parsing of
generic tests. Along the way I reformatted the message returned
from TestBuilder to play nicely with the the existing formatting of
`_parse_generic_test`'s exception handling code.

I've added a basic test to confirm that the approriate
CompilationException when a custom macro is referenced
in a generic test config.

Thanks to @emmyoop for the recommendation that this be listed as a Fix change instead of an "Under the Hood" change!

Co-authored-by: Emily Rockman <[email protected]>

I've simplified the error message raised during a Compilation Error
sourced from a test config. Mainly by way of removing tabs and newlines
where not required.

This commit moves a format call to a multiline fstring in the
schemas.py file for CompilationExceptions.