limit parallelism for resource mounting to 4

this should work around issues like the following:
- https://forum.fivem.net/t/unable-to-join-most-servers-too-many-threads/12209
- https://forum.fivem.net/t/fivem-has-encountered-an-fatal-error/11904
- https://forum.fivem.net/t/error-while-joining-a-server/12426

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=fe6ee92dd2fa14da643766b5e8b3e73c99e34bfd

components/citizen-resources-client/src/CachedResourceMounter.cpp

@@ -19,12 +19,27 @@
 
 #include <network/uri.hpp>
 
+#include <ppl.h>
+
 #include <Error.h>
 
 using fx::CachedResourceMounter;
 
 void MountResourceCacheDevice(std::shared_ptr<ResourceCache> cache);
 
+static auto g_limitedScheduler = concurrency::Scheduler::Create(
+	concurrency::SchedulerPolicy(2, 
+		concurrency::MinConcurrency, 1, 
+		concurrency::MaxConcurrency, 4));
+
+static struct : public concurrency::scheduler_interface
+{
+	virtual void schedule(concurrency::TaskProc_t proc, void* arg) override
+	{
+		g_limitedScheduler->ScheduleTask(proc, arg);
+	}
+} g_schedulerWrap;
+
 CachedResourceMounter::CachedResourceMounter(fx::ResourceManager* manager)
 	: m_manager(manager)
 {
@@ -149,7 +164,7 @@ concurrency::task<fwRefContainer<fx::Resource>> CachedResourceMounter::LoadResou
 				}
 
 				return localResource;
-			});
+			}, concurrency::task_options(g_schedulerWrap));
 		}
 	}