Fix the topic of the notifications sent on the bus

In the fedmsg world this was done by the modname passed to the
fedmsg.publish() function but in fedora-messaging there is no
such concept, so we need to pass the exact/correct topic.
This commit fixes that.

Signed-off-by: Pierre-Yves Chibon <pingou@pingoured.fr>

scripts/httpd/upload.cgi

@@ -193,7 +193,7 @@ def emit_fedora_message(config, name, checksum, filename, username, msgpath):
         )
 
         msg = fedora_messaging.api.Message(
-            topic="lookaside.new",
+            topic="git.lookaside.new",
             body=message
         )
         fedora_messaging.api.publish(msg)