encrypt_client_secret_on_first_use: Encode error with no client_secret

[athoms]

Hi,

when encrypt_client_secret_on_first_use is set to True and one or more account sections have no client_secret entry, this

email-oauth2-proxy/emailproxy.py

Lines 424 to 425 in d1a7421

	if AppConfig.globals().getboolean('encrypt_client_secret_on_first_use', fallback=False):
	config.set(username, 'client_secret_encrypted', OAuth2Helper.encrypt(fernet, client_secret))

throws AttributeError("'NoneType' object has no attribute 'encode'") after getting the access token.

A simple fix would be:

if client_secret and AppConfig.globals().getboolean('encrypt_client_secret_on_first_use', fallback=False):

[simonrob]

Thanks for reporting this.