LegalFilePathsOnly_rejects_arguments_containing_invalid_path_characters failing after update to .NET SDK RC1

[tmat]

https://ci.dot.net/job/dotnet_CliCommandLineParser/job/release_2.1.3xx/job/debug_windows_nt_x64_prtest/17/artifact/artifacts/Debug/TestResults/Microsoft.DotNet.Cli.CommandLine.Tests_netcoreapp2.0_x64.log

      Expected collection {empty} to be equivalent to {"|||"}, but it misses {"|||"}.
      Stack Trace:
        C:\projects\fluentassertions-vf06b\Src\FluentAssertions.Net45\Execution\XUnit2TestFramework.cs(32,0): at FluentAssertions.Execution.XUnit2TestFramework.Throw(String message)
        C:\projects\fluentassertions-vf06b\Src\Core\Execution\AssertionScope.cs(197,0): at FluentAssertions.Execution.AssertionScope.FailWith(String message, Object[] args)
        C:\projects\fluentassertions-vf06b\Src\Core\Collections\CollectionAssertions.cs(364,0): at FluentAssertions.Collections.CollectionAssertions`2.BeEquivalentTo[T](IEnumerable`1 expected, String because, Object[] becauseArgs)
        C:\projects\fluentassertions-vf06b\Src\Core\Collections\StringCollectionAssertions.cs(41,0): at FluentAssertions.Collections.StringCollectionAssertions.BeEquivalentTo(String[] elements)
        /_/src/tests/CommandLine.Tests/ParsingValidationTests.cs(116,0): at Microsoft.DotNet.Cli.CommandLine.Tests.ParsingValidationTests.LegalFilePathsOnly_rejects_arguments_containing_invalid_path_characters()
      Output:
        124
0
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31

The test is now skipped.

[tmat]

@livarcocc FYI