Document why .NET 4.5 is needed

Author: slonopotamus

ue4docker/dockerfiles/ue4-build-prerequisites/windows/install-prerequisites.bat

@@ -57,7 +57,8 @@ if "%VISUAL_STUDIO_BUILD_NUMBER%" == "15" (
 
 @rem Install the Visual Studio Build Tools workloads and components we need
 @rem NOTE: We use the Visual Studio 2022 installer even for Visual Studio 2019 and 2017 here because the old (2017) installer now breaks
-@rem NOTE: Microsoft.NetCore.Component.SDK only exists for VS2019. And it is actually *needed* only for UE5
+@rem NOTE: Microsoft.NetCore.Component.SDK only exists for VS2019+. And it is actually *needed* only for UE5
+@rem NOTE: .NET 4.5 is required for some programs even in UE5, for example https://github.com/EpicGames/UnrealEngine/blob/5.0.1-release/Engine/Source/Programs/UnrealSwarm/SwarmCoordinator/SwarmCoordinator.csproj#L26
 curl --progress-bar -L "https://aka.ms/vs/17/release/vs_buildtools.exe" --output %TEMP%\vs_buildtools.exe || goto :error
 %TEMP%\vs_buildtools.exe --quiet --wait --norestart --nocache ^
 	--installPath C:\BuildTools ^