Fix the import order for D51126461 (#610)

Summary:
Pull Request resolved: #610

In D51126461, we did not import the library according to the alphabetical order, therefore triggering some linter test failure. We therefore made this diff to fix it.

Reviewed By: lucamelis

Differential Revision: D51166750

fbshipit-source-id: 7dd441b49728a63502a6a3f536559e754ccae576

Author: HuanyuZhang

opacus/tests/batch_memory_manager_test.py

@@ -16,7 +16,7 @@
 
 import torch
 import torch.nn as nn
-from hypothesis import given, settings, HealthCheck
+from hypothesis import HealthCheck, given, settings
 from hypothesis import strategies as st
 from opacus import PrivacyEngine
 from opacus.utils.batch_memory_manager import BatchMemoryManager

opacus/tests/privacy_engine_test.py

@@ -26,7 +26,7 @@
 import torch
 import torch.nn as nn
 import torch.nn.functional as F
-from hypothesis import given, settings, HealthCheck
+from hypothesis import HealthCheck, given, settings
 from opacus import PrivacyEngine
 from opacus.layers.dp_multihead_attention import DPMultiheadAttention
 from opacus.optimizers.optimizer import _generate_noise