fix: Update flow.py

[octaflop]

This commit fixes a case in which a user has deleted the token.json and attempts to reauthorize. The user will find the reauthorization to work, but without the prompt=consent query parameter being sent to google's oauth, no new refresh_token will be sent.

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Fixes #348 🦕

Feel free to make any other changes / updates.

personal workaround:

url_args = {
    'access_type': 'offline',
    'prompt': 'consent'
}
flow = InstalledAppFlow.from_client_secrets_file(
    str(credentials_path), SCOPES)
try:
    creds = flow.run_local_server(port=8080, open_browser=False, **url_args)

except MismatchingStateError:
    print("State mismatch error during OAuth process. Trying again...")
    creds = flow.run_local_server(port=8080, open_browser=False, **url_args)

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