Do not fail test for missing initial environment variables that were empty
Do not fail test for missing initial environment variables that were empty

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