Address Pandas to_datetime Warnings

[kiran94]

Currently if you run with pandas 2.2.0 the tool will still run but generate the following errors:

/home/kiran/Documents/playground/prfiesta_test/.venv/lib/python3.11/site-packages/prfiesta/coll
ectors/github.py:157: FutureWarning: errors='ignore' is deprecated and will raise in a future
version. Use to_datetime without passing `errors` and catch exceptions explicitly instead
  df[col] = pd.to_datetime(df[col], errors="ignore")
/home/kiran/Documents/playground/prfiesta_test/.venv/lib/python3.11/site-packages/prfiesta/coll
ectors/github.py:157: FutureWarning: errors='ignore' is deprecated and will raise in a future
version. Use to_datetime without passing `errors` and catch exceptions explicitly instead
  df[col] = pd.to_datetime(df[col], errors="ignore")
/home/kiran/Documents/playground/prfiesta_test/.venv/lib/python3.11/site-packages/prfiesta/coll
ectors/github.py:157: FutureWarning: errors='ignore' is deprecated and will raise in a future
version. Use to_datetime without passing `errors` and catch exceptions explicitly instead
  df[col] = pd.to_datetime(df[col], errors="ignore")