all: make newer pycodestyle happy

Apparently the "two empty lines" rule is now stricter.

fdroidserver/stats.py

@@ -41,6 +41,7 @@ def carbon_send(key, value):
     s.sendall(msg)
     s.close()
 
+
 options = None
 config = None
 
@@ -299,5 +300,6 @@ def main():
 
     logging.info("Finished.")
 
+
 if __name__ == "__main__":
     main()