reduce amount of runs

src/catchup.py

@@ -154,6 +154,7 @@ async def run(PROGRAM_ARGS):
                 if safe_to_post_tweets:
                     if await process_queue():
                         print("Finished processing queue")
+                        return
                     else:
                         print('Posted no new tweets; we\'re caught up!')
                         return
@@ -178,4 +179,4 @@ async def run(PROGRAM_ARGS):
             await queue_loop()
     except KeyboardInterrupt:
         print('Interrupt received. Ending catchup mode...')
-        return False
+        return False