Aim path traversal in LockManager.release_locks

A vulnerability in the `LockManager.release_locks` function in aimhubio/aim (commit bb76afe) allows for arbitrary file deletion through relative path traversal. The `run_hash` parameter, which is user-controllable, is concatenated without normalization as part of a path used to specify file deletion. This vulnerability is exposed through the `Repo._close_run()` method, which is accessible via the tracking server instruction API. As a result, an attacker can exploit this to delete any arbitrary file on the machine running the tracking server.