[compiler-rt] Delete unused test shell scripts (#100889)

This patch deletes two shell scripts in compiler-rt/builtiins/Unit that
seemed to have been used to run the tests at some point, but not
anymore.

They were originally copied over in
8c1441f,
but have only been updated once since in what seemed like a simple grep.

These files also got lit testing support about seven years ago in
9b7bbec that I believe makes these
scripts completely redundant.

Author: boomanaiden154