HttpServer audio and thumbnail lookups explicitly only support GET -- I

think we were doing some unnecessary process with HEAD (and potentially
OPTIONS) requests.

src/plugins/websocket_remote/HttpServer.cpp

@@ -318,6 +318,7 @@ int HttpServer::HandleRequest(
     int status = MHD_HTTP_NOT_FOUND;
 
     try {
+        if (method && std::string(method) == "GET") {
             if (!isAuthenticated(connection, server->context)) {
                 status = 401; /* unauthorized */
                 static const char* error = "unauthorized";
@@ -349,6 +350,7 @@ int HttpServer::HandleRequest(
                 }
             }
         }
+    }
     catch (...) {
     }