v1.2 Appservice login type identifier inconsistency

[Schuwi]

Link to problem area:

https://spec.matrix.org/v1.2/client-server-api/#appservice-login

Issue
The appservice login type is referred to as m.login.appservice here while in the Application Service API spec it's specified as m.login.application_service, same as in the corresponding MSC2778 and the /register route.

Expected behaviour
The identifier in Client-Server API and Application Service API specs should be consistent. I suppose the correct identifier is m.login.application_service.

[Half-Shot]

Looks like it didn't get copied into the spec properly, it's actually m.login.application_service in Synapse anyway (https://github.com/matrix-org/synapse/blob/2f053f3f82ca174cc1c858c75afffae51af8ce0d/synapse/rest/client/login.py#L73-L74) so it looks like even implementations are following the proposal.