cltest: Fix leaked_handle

While performing static tool analysis using coverity found
following reports for resouse leak

bluez-5.64/tools/cltest.c:75: leaked_handle: Handle variable "fd"
going out of scope leaks the handle.

tools/cltest.c

@@ -72,6 +72,7 @@ static bool send_message(const bdaddr_t *src, const bdaddr_t *dst,
 		return false;
 	}
 
+	close(fd);
 	return true;
 }