Added debug text that confirms DHCP releases socket.

Author: BiffoBear

adafruit_wiznet5k/adafruit_wiznet5k_dhcp.py

@@ -219,6 +219,7 @@ def _socket_release(self) -> None:
         if self._wiz_sock:
             self._eth.socket_close(self._wiz_sock)
             self._wiz_sock = None
+        debug_msg("  Socket released.", self._debug)
 
     def _dhcp_connection_setup(self, timeout: float = 5.0) -> None:
         """Initialise a UDP socket.