Fix oauth2 session gob register (#36017)

`gob.Register` must be called before Sessioner

Fix #36016

modules/auth/webauthn/webauthn.go

@@ -22,7 +22,7 @@ var WebAuthn *webauthn.WebAuthn
 
 // Init initializes the WebAuthn instance from the config.
 func Init() {
-	gob.Register(&webauthn.SessionData{})
+	gob.Register(&webauthn.SessionData{}) // TODO: CHI-SESSION-GOB-REGISTER.
 
 	appURL, _ := protocol.FullyQualifiedOrigin(setting.AppURL)