Make registry thread sleep

This patch adds a required sleep of 1 second in each
registry thread loop to prevent runaway cpu usage

aprsd/threads/registry.py

@@ -1,4 +1,5 @@
 import logging
+import time
 
 from oslo_config import cfg
 import requests
@@ -50,4 +51,5 @@ class APRSRegistryThread(aprsd_threads.APRSDThread):
             except Exception as e:
                 LOG.error(f"Failed to send registry info: {e}")
 
+        time.sleep(1)
         return True