Remove LoadFromAssemblyName for MSBuild assemblies in the CoreCLRAssemblyLoader (#3900)
Remove LoadFromAssemblyName for MSBuild assemblies in the CoreCLRAssemblyLoader (#3900)

Search for known assemblies in the same path as `Microsoft.Build.dll`.

Fixes #3352
rainersigwald/msbuild,jeffkl/msbuild,chipitsine/msbuild,rainersigwald/msbuild,Microsoft/msbuild,mono/msbuild,rainersigwald/msbuild,mono/msbuild,sean-gilliam/msbuild,jeffkl/msbuild,Microsoft/msbuild,jeffkl/msbuild,AndyGerlicher/msbuild,Microsoft/msbuild,chipitsine/msbuild,mono/msbuild,cdmihai/msbuild,mono/msbuild,AndyGerlicher/msbuild,cdmihai/msbuild,cdmihai/msbuild,sean-gilliam/msbuild,sean-gilliam/msbuild,cdmihai/msbuild,rainersigwald/msbuild,jeffkl/msbuild,AndyGerlicher/msbuild,AndyGerlicher/msbuild,sean-gilliam/msbuild,Microsoft/msbuild,chipitsine/msbuild,chipitsine/msbuild