upgrading pyarrow to fix the numpy 1.21.0 broken changes and fixing integ tests

[NikhilRaverkar]

Issue #, if available:

1. Updated pyarrow version to 3.0.0 to fix the broken changes with numoy 1.21.0
2. Fixed broken integ tests

Description of changes:
Fixed pyarrow version

Testing:
Verified that error does not exist anymore after the upgrade:

>>> import pandas as pd
>>> df = pd.DataFrame({'x': [1,2]})
>>> df.to_parquet('test.parquet', engine='pyarrow')
>>> print(pd.__version__)
1.1.3
>>> print(pyarrow.__version__)
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
NameError: name 'pyarrow' is not defined
>>> import pyarrow
>>> print(pyarrow.__version__)
4.0.0
>>> import numpy
>>> print(numpy.__version__)
1.21.0
>>> 

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[secastillo]

for my understanding, why were these arguments module_dir and model_dir added with these changes?

[NikhilRaverkar]

Sorry for the confusion, these changes are unrelated to the pyarrow upgrade. The integ tests are currently broken so this change is fixing the integ tests as well. Updated description and title

[dewan-c]

Do we also want to update the version in test setup(tox.ini)?

[NikhilRaverkar]

Good catch! updated

[NikhilRaverkar]

Closing this since PR#110 is upgrading the version. Will create a new PR for the new version