Fixed #22419 -- Typo in docs/topics/db/multi-db.txt.

Thanks Josh Kupershmidt.

docs/topics/db/multi-db.txt

@@ -699,6 +699,6 @@ connecting to external databases. Therefore, it's recommended:
 
 .. warning::
 
-    If you're synchronizing content types to more that one database, be aware
+    If you're synchronizing content types to more than one database, be aware
     that their primary keys may not match across databases. This may result in
     data corruption or data loss.