telemetry_json: Remove unnecessary includes

Removes unused includes. Also rectifies a missing <chrono> include.

src/web_service/telemetry_json.cpp

@@ -2,8 +2,6 @@
 // Licensed under GPLv2 or any later version
 // Refer to the license.txt file included.
 
-#include <thread>
-#include "common/assert.h"
 #include "common/detached_tasks.h"
 #include "web_service/telemetry_json.h"
 #include "web_service/web_backend.h"

src/web_service/telemetry_json.h

@@ -5,6 +5,7 @@
 #pragma once
 
 #include <array>
+#include <chrono>
 #include <string>
 #include <json.hpp>
 #include "common/announce_multiplayer_room.h"