Revert back to splitting the tests

Author: SeanNaren

tests/plugins/test_sharded_plugin.py

@@ -4,7 +4,6 @@
 import pytest
 import torch
 
-import tests.helpers.utils as tutils
 from pytorch_lightning import Trainer
 from pytorch_lightning.callbacks import Callback
 from pytorch_lightning.plugins import DDPShardedPlugin, DDPSpawnShardedPlugin
@@ -298,13 +297,24 @@ def training_step(self, batch, batch_idx):
 
 
 @RunIf(skip_windows=True, special=True, fairscale=True, min_gpus=2)
-@pytest.mark.parametrize("accelerator", ["ddp_sharded"])
-def test_ddp_sharded_plugin_manual_optimization(tmpdir, accelerator):
-    tutils.set_random_master_port()
+def test_ddp_sharded_plugin_manual_optimization_spawn(tmpdir):
+    # todo (sean): this test has been split out as running both tests using parametrize causes "Address in use"
     model = ManualBoringModel()
     trainer = Trainer(
         default_root_dir=tmpdir,
-        accelerator=accelerator,
+        accelerator='ddp_sharded_spawn',
+        fast_dev_run=2,
+        gpus=2,
+    )
+    trainer.fit(model)
+
+
+@RunIf(skip_windows=True, special=True, fairscale=True, min_gpus=2)
+def test_ddp_sharded_plugin_manual_optimization(tmpdir):
+    model = ManualBoringModel()
+    trainer = Trainer(
+        default_root_dir=tmpdir,
+        accelerator='ddp_sharded',
         fast_dev_run=2,
         gpus=2,
     )