Add .gitignore entry to ignore local sherlock clone

[GOOFY767]

Why:
A local clone of the external sherlock repository was created inside the workspace. This change prevents accidentally committing that nested git repository into this repo.

What I changed:

• Adds sherlock/ to the repository .gitignore so the cloned directory is ignored.

Notes for reviewers:

• This intentionally avoids adding a nested git repository as tracked files. If the intent is to track or vendor sherlock, consider adding it as a submodule or using a different approach.