ResGen doesn't properly declare its dependency on PrepareResourceNames

It is implied that the `ResGen` target needs to run after `PrepareResourceNames`:
https://github.com/dotnet/msbuild/blob/6278211736efa2b12cd6cae38572692a44889632/src/Tasks/Microsoft.Common.CurrentVersion.targets#L2991-L2992

It is important because CoreResGen relies on the `%(ManifestResourceName)` metadata being set on the `@(EmbeddedResource)` items:
https://github.com/dotnet/msbuild/blob/6278211736efa2b12cd6cae38572692a44889632/src/Tasks/Microsoft.Common.CurrentVersion.targets#L3272

The metadata is being set in the `CreateManifestResourceNames` target:
https://github.com/dotnet/msbuild/blob/6278211736efa2b12cd6cae38572692a44889632/src/Tasks/Microsoft.CSharp.CurrentVersion.targets#L92

**However**, `ResGen` doesn't explicitly declare its dependency on `PrepareResourceNames`, and in fact, it is possible that a poorly written target can cause `ResGen` to run before `PrepareResourceNames`. Here's an example:

```

GenerateResourceToMergeWithCTO

CoreResGen

MergeCtoResource;
PrepareResourceNames;
ResGen;


CreateManifestResourceNames;


PrepareResources;


CoreBuild;

```

Here we can see that `ResGen` runs before `PrepareResourceNames`: