[lit] Remove %T from tests
This patch removes %T from tests in preparation for removing the
substitution completely. Splitting this off from the actual removal to
make it easier to revert the removal of %T in case I missed something.
Reviewers: RKSimon, jh7370, cmtice, petrhosek, ilovepi, pogo59
Reviewed By: cmtice, RKSimon, jh7370
Pull Request: https://github.com/llvm/llvm-project/pull/160027
