[unit test] add megatron init test in zero_optim (#1358)

tests/test_tensor/test_zero_optim.py

@@ -18,6 +18,7 @@ from colossalai.testing import parameterize
 from colossalai.amp import convert_to_apex_amp
 from colossalai.gemini.gemini_mgr import GeminiManager
 from colossalai.tensor import ColoTensorSpec, ShardSpec, ComputePattern, ComputeSpec, ProcessGroup, ColoTensor
+from tests.test_tensor.model.test_gpt2 import init_megatron_spec
 
 
 def check_param_equal(model, torch_model, pg: ProcessGroup):
@@ -127,10 +128,10 @@ def run_dist(rank, world_size, port):
     config = {}
     colossalai.launch(config=config, rank=rank, world_size=world_size, host='localhost', port=port, backend='nccl')
     if world_size == 4:
-        run_gpt(tp_init_spec_func=init_1d_col_spec)
-        run_gpt(tp_init_spec_func=init_1d_row_spec)
+        run_gpt(tp_init_spec_func=init_megatron_spec)
     else:
         run_gpt(tp_init_spec_func=init_1d_col_spec)
+        run_gpt(tp_init_spec_func=init_1d_row_spec)
 
 
 @pytest.mark.dist