Bump pyarrow from 4.0.0 to 4.0.1

Bumps [pyarrow](https://arrow.apache.org/) from 4.0.0 to 4.0.1.

requirements.txt

@@ -6,7 +6,7 @@ mlxtend==0.18.0
 numba==0.53.1
 numpy==1.20.2
 outlier-utils==0.0.3
-pyarrow==4.0.0
+pyarrow==4.0.1
 pandas==1.2.4
 pytest==6.2.3
 pytest-lazy-fixture==0.6.3