[CI] Update test markers and configurations to use 'full_model' for L4 nightly tests (#2641)

Signed-off-by: wangyu <410167048@qq.com>

tests/distributed/omni_coordinator/test_omni_coord_client_for_stage.py

@@ -17,8 +17,6 @@ from vllm_omni.distributed.omni_coordinator import (
 
 pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
 
-pytestmark = [pytest.mark.core_model, pytest.mark.cpu]
-
 
 def _bind_router() -> tuple[zmq.Context, zmq.Socket, str]:
     ctx = zmq.Context.instance()