Reorganize conditional branches to improve readability

Signed-off-by: Joffrey F <joffrey@docker.com>

compose/progress_stream.py

@@ -19,9 +19,12 @@ def stream_output(output, stream):
         if not is_progress_event:
             print_output_event(event, stream, is_terminal)
             stream.flush()
+            continue
+
+        if not is_terminal:
+            continue
 
         # if it's a progress event and we have a terminal, then display the progress bars
-        elif is_terminal:
         image_id = event.get('id')
         if not image_id:
             continue