Pg fix: drop NOT NULL constraint from user ban

Author: jagerman

sogs/db.py

@@ -550,7 +550,7 @@ def user_perm_future_updates(conn):
         conn.execute(
             """
 CREATE TABLE user_ban_futures (
-    room INTEGER NOT NULL REFERENCES rooms ON DELETE CASCADE,
+    room INTEGER REFERENCES rooms ON DELETE CASCADE,
     "user" INTEGER NOT NULL REFERENCES users ON DELETE CASCADE,
     at FLOAT NOT NULL, /* when the change should take effect (unix epoch) */
     banned BOOLEAN NOT NULL /* if true then ban at `at`, if false then unban */

sogs/schema.pgsql

@@ -376,7 +376,7 @@ CREATE INDEX user_permissions_future_room_user ON user_permission_futures(room,
 -- their user_permissions.banned to TRUE then add a row here with banned = FALSE to schedule the
 -- unban.  (You can also schedule a future *ban* here, but the utility of that is less clear).
 CREATE TABLE user_ban_futures (
-    room INTEGER NOT NULL REFERENCES rooms ON DELETE CASCADE,
+    room INTEGER REFERENCES rooms ON DELETE CASCADE,
     "user" INTEGER NOT NULL REFERENCES users ON DELETE CASCADE,
     at FLOAT NOT NULL, /* when the change should take effect (unix epoch) */
     banned BOOLEAN NOT NULL /* if true then ban at `at`, if false then unban */