[common] remove DetachedTasks object usage (#4096)

this was only ever used for announce room json on one single instance

this object is pretty much a danger to society and shouldnt exist, especially since its:
a) a singleton
b) spawns objects out of thin air
c) doesn't respect RAII and can outlive its parent objects (big no no)

generally we shouldnt endorse objects like these in the future, but alas, it existed, now it has to begone
additionally there is a similar object in KWorkerTaskManager but it's not as egregious as this one.
check that this didnt break the usual announce room json logic

Signed-off-by: lizzie <lizzie@eden-emu.dev>

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/4096
Reviewed-by: CamilleLaVey <camillelavey99@gmail.com>
Reviewed-by: MaranBr <maranbr@eden-emu.dev>

src/android/app/src/main/jni/native.cpp

@@ -39,7 +39,6 @@
 #include "common/android/multiplayer/multiplayer.h"
 #include "common/android/android_common.h"
 #include "common/android/id_cache.h"
-#include "common/detached_tasks.h"
 #include "common/dynamic_library.h"
 #include "common/fs/path_util.h"
 #include "common/logging.h"
@@ -352,7 +351,6 @@ void EmulationSession::ShutdownEmulation() {
     if (m_load_result == Core::SystemResultStatus::Success) {
         m_system.DetachDebugger();
         m_system.ShutdownMainProcess();
-        m_detached_tasks.WaitForAllTasks();
         m_load_result = Core::SystemResultStatus::ErrorNotInitialized;
         m_window.reset();
         OnEmulationStopped(Core::SystemResultStatus::Success);

src/android/app/src/main/jni/native.h

@@ -6,7 +6,6 @@
 
 #include <android/native_window_jni.h>
 #include "common/android/applets/software_keyboard.h"
-#include "common/detached_tasks.h"
 #include "core/core.h"
 #include "core/file_sys/registered_cache.h"
 #include "core/hle/service/acc/profile_manager.h"
@@ -75,7 +74,6 @@ private:
     // Core emulation
     Core::System m_system;
     InputCommon::InputSubsystem m_input_subsystem;
-    Common::DetachedTasks m_detached_tasks;
     Core::PerfStatsResults m_perf_stats{};
     int m_shaders_building{0};
     std::shared_ptr<FileSys::VfsFilesystem> m_vfs;