Fix AssemblyProcessor builds.

[ericwj]

PR Details

Fixes problems with the AssemblyProcessor solution and how it is used throughout Stride.

Description

• Clean up the projects in the AssemblyProcessor solution and have them build for net472 and net6.0.
• Remove assembly binding redirection configuration because all related issues are solved by disregarding the netstandard2.0 TFM.
• Update Stride.Core.targets in two places (two files) to select the right version of AssemblyProcessor to use depending on MSBuildRuntimeType.
• Stride.GameStudio selects the version of the AssemblyProcessor DLL to use with [MSBuild]::IsTargetFrameworkCompatible.
• Update Stride.GameStudio version of Mono.Cecil to match the version used by the AssemblyProcessor DLL.

Related Issue

#1479

Motivation and Context

Fixes errors and warnings in the AssemblyProcessor solution. Simplifies making changes to the assembly processor which I might want to make to obtain diagnostics and verify that it does or doesn't do certain things (anymore).

Types of changes

• [x] ~Docs change / refactoring~ / dependency upgrade
• [x] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [x] Breaking change (fix or feature that would cause existing functionality to change)
  • [x] Taking the PR as-is will break master since it deletes the DLL's in deps\AssemblyProcessor. A followon PR by someone able to update those files and potentially signing them etc is needed to make this change non-breaking. In the mean time, the instruction is to open and build Stride.AssemblyProcessor.sln before attempting to build Stride.sln.

Checklist

• [ ] My change requires a change to the documentation.
• [ ] I have added tests to cover my changes.
• [x] All new and existing tests passed. Yes, the tests in the assembly processor solution now 1) compile and 2) succeed.