GoogleTest: Fix escaping in test names

Due to add_command() being a macro it introduced excessive and
nonobvious escaping in different parts of the script. Because of
one of such places the resulting script would have an erroneous
${TEST_LIST} if the user data (in test parameters) had a semicolon.

To eliminate this non-obvious escaping, add_command() was converted
to function. Updated the escaping accordingly.

Fixes: #23059
8 files changed