refactor: Simplify testing with ScopedTritonServer instead of pytest fixtures

[KrishnanPrash]

This PR has been raised to address Jira Ticket [DLIS-6803]

Replaces the existing (pytest.fixture and generator) approach with ScopedTritonServer, a context manager, that starts and kills the server.

Specific features being added/addressed in this PR:

• Eliminates the need for pytest.fixture to kill the background server.
• Eliminates the need for generators to kill the background server.
• Reduces the number of server-related arguments passed to the testing functions
• Context Manager (ScopedTritonServer) abstracts away process id logic from the test functions
• ScopedTritonServer Functions:
  • __enter__(): Sends start up command and polls until server is ready
  • __exit__(): Kills the server