Since cbd1003d9d I'm able to add _some_
invalid config definitions to modules the tests are using and get no
build error.
For example `extraConfigLua = null;` should produce an invalid type
error, but doesn't.
One less visible change in that commit is the move away from using the
"standalone" wrapper (`makeNixvimWithModule`), which implicitly sets
`wrapRc = true`.
Adding back `wrapRc` to the tests seems to fix the issue, however this
makes me wonder if there's an underlying issue with wrapping/not-wrapping?
Perhaps we've simply uncovered a long-standing eval issue that is masked
over by using `wrapRc`?