rabbit_prelaunch_conf: Remove out-of-date comment

We already try both formats when we parse the configuration.

Author: dumbbell

apps/rabbitmq_prelaunch/src/rabbit_prelaunch_conf.erl

@@ -21,7 +21,6 @@ setup(Context) ->
     %% TODO: Check if directories/files are inside Mnesia dir.
 
     %% TODO: Support glob patterns & directories in RABBITMQ_CONFIG_FILE.
-    %% TODO: Always try parsing of both erlang and cuttlefish formats.
 
     ok = set_default_config(),