cachedTypes in AssemblyNamesTypeResolutionService is unreachable

**Problem description:**

[Here ](https://github.com/dotnet/winforms/blob/master/src/System.Windows.Forms/src/System/Resources/ResXDataNode.cs#L977) the field [cachedTypes](https://github.com/dotnet/winforms/blob/master/src/System.Windows.Forms/src/System/Resources/ResXDataNode.cs#L824) is currently unreachable because it relies on `Assembly.GlobalAssemblyCache` which is false in .NET Core and `IsNetFrameworkAssembly`, which is also always false because it tests if assembly `Location` path is .NET Framework path, while (on Windows) .NET Core assemblies are on `C:\Program Files\dotnet\shared\Microsoft.NETCore.App\...` path.

**Actual behavior:**

Types are not cached

**Expected behavior:**

.NET Core types are cached (?)