Missing ciso8601 in Pnnotdb 0.4.7

[potiuk]

Airflow canary builds started to fail after last pintodb release:

Example here:
https://github.com/apache/airflow/actions/runs/3133775825/jobs/5087788714#step:10:9254

Seems that the recent release has a hidden dependency on ciso8601 package, but it missing in install_requires.

  ______ ERROR collecting tests/providers/apache/pinot/hooks/test_pinot.py _______
  ImportError while importing test module '/opt/airflow/tests/providers/apache/pinot/hooks/test_pinot.py'.
  Hint: make sure your test modules/packages have valid Python names.
  Traceback:
  /usr/local/lib/python3.8/importlib/__init__.py:127: in import_module
      return _bootstrap._gcd_import(name[level:], package, level)
  tests/providers/apache/pinot/hooks/test_pinot.py:29: in <module>
      from airflow.providers.apache.pinot.hooks.pinot import PinotAdminHook, PinotDbApiHook
  airflow/providers/apache/pinot/hooks/pinot.py:24: in <module>
      from pinotdb import connect
  /usr/local/lib/python3.8/site-packages/pinotdb/__init__.py:1: in <module>
      from pinotdb.db import connect, connect_async
  /usr/local/lib/python3.8/site-packages/pinotdb/db.py:2: in <module>
      import ciso8601
  E   ModuleNotFoundError: No module named 'ciso8601'