[lldb][PlatformDarwin][test] Add unit-test for LocateExecutableScriptingResourcesFromDSYM (#185057)
Depends on:
* https://github.com/llvm/llvm-project/pull/185056
Adds test unit-test for
`PlatformDarwin::LocateExecutableScriptingResourcesFromDSYM`. I had to
mock the `ScriptInterpreter` because the function internally uses the
`ScriptInterpreterPython` to check for reserved words in file names. But
linking the `ScriptInterpreterPython` was quite the undertaking, which I
think we could pull off, but required more churn that I had hoped.
Mocking it seemed pretty low-cost so I resorted to doing that instead.
Test-cases aren't very elaborate yet. It just has a basic assertion that
we locate the Python file within the dSYM. Mostly I set up
infrastructure for future test-cases.