Clarify rule 4.3.1 of the auth rules in room version 11 (#2024)

Signed-off-by: Denis Kasak <dkasak@termina.org.uk>

changelogs/room_versions/newsfragments/2024.clarification

@@ -0,0 +1 @@
+Clarify rule 4.3.1 of the auth rules in room version 11 to state which event's `sender` the `state_key` needs to match.

content/rooms/v11.md

@@ -144,7 +144,7 @@ The rules are as follows:
     3.  If `membership` is `join`:
         1.  {{% changed-in v=11 %}}
             If the only previous event is an `m.room.create` and the
-            `state_key` is the sender, allow.
+            `state_key` is the sender of the `m.room.create`, allow.
         2.  If the `sender` does not match `state_key`, reject.
         3.  If the `sender` is banned, reject.
         4.  If the `join_rule` is `invite` or `knock` then allow if