add if-none-match tag to agent put

Author: garemoko

src/RemoteLRS.php

@@ -1072,6 +1072,9 @@ public function saveAgentProfile($agent, $id, $content) {
                 if (isset($options['etag'])) {
                     $requestCfg['headers']['If-Match'] = $options['etag'];
                 }
+                else {
+                    $requestCfg['headers']['If-None-Match'] = '*';
+                }
             }
         }