Small edits to actioncable/CHANGELOG.md

[ci skip]

- capitalize WebSocket

actioncable/CHANGELOG.md

@@ -13,12 +13,12 @@
 
     *Vladimir Dementyev*
 
-*   Buffer now writes to websocket connections, to avoid blocking threads
+*   Buffer now writes to WebSocket connections, to avoid blocking threads
     that could be doing more useful things.
 
     *Matthew Draper*, *Tinco Andringa*
 
-*   Protect against concurrent writes to a websocket connection from
+*   Protect against concurrent writes to a WebSocket connection from
     multiple threads; the underlying OS write is not always threadsafe.
 
     *Tinco Andringa*