Save the authentication method on each authorization

This will help us logging out of the upstream.

crates/storage-pg/migrations/20230828143553_user_session_authentication_source.sql

@@ -0,0 +1,23 @@
+-- Copyright 2023 The Matrix.org Foundation C.I.C.
+--
+-- Licensed under the Apache License, Version 2.0 (the "License");
+-- you may not use this file except in compliance with the License.
+-- You may obtain a copy of the License at
+--
+--     http://www.apache.org/licenses/LICENSE-2.0
+--
+-- Unless required by applicable law or agreed to in writing, software
+-- distributed under the License is distributed on an "AS IS" BASIS,
+-- WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+-- See the License for the specific language governing permissions and
+-- limitations under the License.
+
+-- This adds the source of each authentication of a user_session
+ALTER TABLE "user_session_authentications"
+    ADD COLUMN "user_password_id" UUID
+        REFERENCES "user_passwords" ("user_password_id")
+        ON DELETE SET NULL,
+
+    ADD COLUMN "upstream_oauth_authorization_session_id" UUID
+        REFERENCES "upstream_oauth_authorization_sessions" ("upstream_oauth_authorization_session_id")
+        ON DELETE SET NULL;