Fix example MXC URI for m.presence

Signed-off-by: Aaron Raimist <[email protected]>

Author: aaronraimist

data/event-schemas/examples/m.presence.yaml

@@ -3,7 +3,7 @@
   "sender": "@example:localhost",
   "type": "m.presence",
   "content": {
-    "avatar_url": "mxc://localhost:wefuiwegh8742w",
+    "avatar_url": "mxc://localhost/wefuiwegh8742w",
     "last_active_ago": 2478593,
     "presence": "online",
     "currently_active": false,