test(dtr): make dtr_resnet1202 isolated

GitOrigin-RevId: 4d863cc32e4bd88db5d9ffedb33af088958c4bbb

imperative/python/test/integration/test_dtr.py

+import multiprocessing as mp
+
 import numpy as np
 import pytest
 
@@ -88,8 +90,7 @@ class ResNet(M.Module):
         return out
 
 
-@pytest.mark.require_ngpu(1)
-def test_dtr_resnet1202():
+def run_dtr_resnet1202():
     batch_size = 8
     resnet1202 = ResNet(BasicBlock, [200, 200, 200])
     opt = optim.SGD(resnet1202.parameters(), lr=0.05, momentum=0.9, weight_decay=1e-4)
@@ -124,3 +125,13 @@ def test_dtr_resnet1202():
 
     t.numpy()
     mge.dtr.disable()
+    mge._exit(0)
+
+
+@pytest.mark.require_ngpu(1)
+@pytest.mark.isolated_distributed
+def test_dtr_resnet1202():
+    p = mp.Process(target=run_dtr_resnet1202)
+    p.start()
+    p.join()
+    assert p.exitcode == 0