Restore CPU LLM Server integration test (#520)

Remove `xfail` from CPU LLM Server Integration test. Shortfin server is
back in a good spot, and this should be left on anyways

build_tools/integration_tests/llm/cpu_llm_server_test.py

@@ -78,15 +78,13 @@ def do_generate(prompt, port):
     ],
     indirect=True,
 )
-@pytest.mark.xfail(raises=AccuracyValidationException)
 def test_llm_server(llm_server, available_port):
     # Here you would typically make requests to your server
     # and assert on the responses
     assert llm_server.poll() is None
     output = do_generate("1 2 3 4 5 ", available_port)
     logger.info(output)
     expected_output_prefix = "6 7 8"
-    # TODO(#437): Remove when accuracy issue from latest iree-compiler RC is resolved.
     if not output.startswith(expected_output_prefix):
         raise AccuracyValidationException(
             f"Expected '{output}' to start with '{expected_output_prefix}'"