add no colocate update critic only #1422

Job	Run time
e2e-test-megatron (8, test_moonlight_16B_A3B.py)	9m 45s
e2e-test-megatron (8, test_qwen3_4B_ppo.py)	13m 8s
e2e-test-megatron (8, test_quick_start_glm4_9B.py)	11m 54s
e2e-test-megatron (0, 8, test_qwen3_30B_A3B_r3.py, 1, 1)	22m 5s
e2e-test-megatron (8, test_mimo_7B_mtp_only_grad.py)	4m 30s
e2e-test-megatron (8, test_qwen3_4B_ppo_train_critic_only.py)	3m 4s
e2e-test-megatron (0, 8, test_qwen3_30B_A3B_r3.py)	12m 4s
e2e-test-megatron (8, test_qwen3_30B_A3B.py, 1, 1)	3m 48s
e2e-test-megatron (0, 8, test_moonlight_16B_A3B_r3.py)	9m 36s
e2e-test-megatron (8, test_qwen2.5_0.5B_debug_rollout_then_train.py)	4m 32s
e2e-test-megatron (8, test_qwen2.5_0.5B_opd_sglang.py)	5m 19s
e2e-test-precision	0s
e2e-test-fsdp	0s
e2e-test-changed-detect	0s
e2e-test-short	0s
e2e-test-ckpt	0s
e2e-test-image	0s
e2e-test-changed	0s
	1h 39m 45s

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