chore(deps): update dependency pyarrow to v2 (#380)

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This PR contains the following updates:

| Package | Update | Change |
|---|---|---|
| [pyarrow](https://arrow.apache.org/) | major | `==1.0.1` -> `==2.0.0` |

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samples/snippets/requirements.txt

@@ -6,5 +6,5 @@ ipython==7.16.1; python_version < '3.7'
 ipython==7.17.0; python_version >= '3.7'
 matplotlib==3.3.3
 pandas==1.1.4
-pyarrow==1.0.1
+pyarrow==2.0.0
 pytz==2020.1