[FRONTEND] Fix unnecessary pylint errors (#15838)

Handle unnecessary pylint errors from these frontends

Author: srkreddy1238

tests/python/frontend/keras/test_forward.py

@@ -28,11 +28,11 @@
 # prevent Keras from using up all gpu memory
 import keras
 
+import pytest
 import tvm
 from tvm import relay
 from tvm.contrib import graph_executor
 import tvm.testing
-import pytest
 
 if tf.executing_eagerly():
     GPUS = tf.config.experimental.list_physical_devices("GPU")

tests/python/frontend/oneflow/test_forward.py

@@ -20,11 +20,11 @@
 
 import numpy as np
 import oneflow as flow
+from packaging import version as package_version
 import tvm
 import tvm.testing
 import tvm.topi.testing
 from tvm import relay
-from packaging import version as package_version
 
 MODEL_HOME = "test_model"