Implement SubscribeToAllFolders attribute to subscription requests

[ecederstrand]

Pull, Push and Streaming subscription requests support a SubscribeToAllFolders attribute. See
https://learn.microsoft.com/en-us/exchange/client-developer/web-service-reference/pullsubscriptionrequest, https://learn.microsoft.com/en-us/exchange/client-developer/web-service-reference/pushsubscriptionrequest, https://learn.microsoft.com/en-us/exchange/client-developer/web-service-reference/streamingsubscriptionrequest

exchangelib should support that flag. Possibly as the default if the subscription is created from Account.root.

Discussed in #1242

^{Originally posted by CubePirate October 30, 2023}
I can't seem to figure out how to create a stream subscription for all folders, does the library support it?
I know EWS does support it, via "<StreamingSubscriptionRequest SubscribeToAllFolders="">"
See https://learn.microsoft.com/en-us/exchange/client-developer/web-service-reference/streamingsubscriptionrequest

[ecederstrand]

Fixed by #1244

[CubePirate]

Wow! That was fast. Thanks Erik!

[ecederstrand]

You're welcome! You can now call the subscription methods directly on the Account object, e.g. some_account.subscribe_to_pull(). That should create a subscription on all folders.