[BUG]Select dtypes fails if list dtypes present in dataframe

[VibhuJawa]

Describe the bug
Select dtypes fails if list dtypes present in dataframe

Steps/Code to reproduce bug

import cudf
df = cudf.DataFrame({'int_col':[0,1,2],'list_col':[[1,2],[3,4],[5,6]]})
df.select_dtypes('int64').columns

---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-3-1632dc06c94a> in <module>
      1 import cudf
      2 df = cudf.DataFrame({'int_col':[0,1,2],'list_col':[[1,2],[3,4],[5,6]]})
----> 3 df.select_dtypes('int64').columns

/nvme/0/vjawa/vjawa_cudf/cudf/python/cudf/cudf/core/dataframe.py in select_dtypes(self, include, exclude)
   6612                 if is_categorical_dtype(i_dtype):
   6613                     include_subtypes.add(i_dtype)
-> 6614                 elif issubclass(dtype.type, i_dtype):
   6615                     include_subtypes.add(dtype.type)
   6616 

TypeError: issubclass() arg 1 must be a class

Expected behavior
The behavior we get without list type

import cudf
df = cudf.DataFrame({'int_col':[0,1,2],'float_col':[1.1,2.2,3.3]})
df.select_dtypes('int64').columns

Index(['int_col'], dtype='object')

Environment overview (please complete the following information)

• Environment location: [Bare-metal]
• Method of cuDF install: [conda]

Environment details

cudf                      0.17.0a201203   cuda_10.2_py37_g5336301b85_372    rapidsai-nightly
libcudf                   0.17.0a201203   cuda10.2_g5336301b85_372    rapidsai-nightly

[github-actions]

This issue has been marked stale due to no recent activity in the past 30d. Please close this issue if no further response or action is needed. Otherwise, please respond with a comment indicating any updates or changes to the original issue and/or confirm this issue still needs to be addressed. This issue will be marked rotten if there is no activity in the next 60d.

[github-actions]

This issue has been labeled inactive-90d due to no recent activity in the past 90 days. Please close this issue if no further response or action is needed. Otherwise, please respond with a comment indicating any updates or changes to the original issue and/or confirm this issue still needs to be addressed.

[galipremsagar]

Closed by #8849