unskip perforce sub-repo perms integration test

Created by: mollylogue

Closes https://github.com/sourcegraph/sourcegraph/issues/40149

Fixed the integration tests and unskip

What was fixed:

• PERFORCE_PASSWORD set to correct value
• p4 protects table in test perforce instance issues resolved

Test plan

Tested locally and it works. Validated that integration tests now pass in CI as well.