verify-nupkgs.ps1 fails when artifacts are signed

[ellahathaway]

verify-nupkgs.ps1 is invalid when the artifacts are signed. Signing adds a .signature.p7s file to a nupkg, which increases the number of actual files in the nupkgs and causes the validation to fail by an offset of +1.

This validation runs after signing as part of this target.

Example output from build with signing enabled:

Unzipping NuGet packages.
  Verify NuGet packages files.
  Verifying package 'Microsoft.TestPlatform.Internal.Uwp.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.CodeCoverage.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.NET.Test.Sdk.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.TestPlatform.AdapterUtilities.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.TestPlatform.Build.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.TestPlatform.CLI.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.TestPlatform.Extensions.TrxLogger.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.TestPlatform.ObjectModel.17.13.0-preview-24523-01'.
  Verifying package 'Microsoft.TestPlatform.TranslationLayer.17.13.0-preview-24523-01'.
  Verify-Nuget-Packages : There are 9 errors:
  Number of files are not equal for 'Microsoft.TestPlatform.Internal.Uwp.17.13.0-preview-24523-01', expected: 38 actual: 
  39
  Number of files are not equal for 'Microsoft.CodeCoverage.17.13.0-preview-24523-01', expected: 59 actual: 60
  Number of files are not equal for 'Microsoft.NET.Test.Sdk.17.13.0-preview-24523-01', expected: 15 actual: 16
  Number of files are not equal for 'Microsoft.TestPlatform.AdapterUtilities.17.13.0-preview-24523-01', expected: 75 
  actual: 76
  Number of files are not equal for 'Microsoft.TestPlatform.Build.17.13.0-preview-24523-01', expected: 20 actual: 21
  Number of files are not equal for 'Microsoft.TestPlatform.CLI.17.13.0-preview-24523-01', expected: 471 actual: 472
  Number of files are not equal for 'Microsoft.TestPlatform.Extensions.TrxLogger.17.13.0-preview-24523-01', expected: 34 
  actual: 35
  Number of files are not equal for 'Microsoft.TestPlatform.ObjectModel.17.13.0-preview-24523-01', expected: 92 actual: 
  93
  Number of files are not equal for 'Microsoft.TestPlatform.TranslationLayer.17.13.0-preview-24523-01', expected: 122 
  actual: 123

I think that the solution here is to either 1) skip the test when signing or 2) modify the test to increase the expected number of files by one when signing.

[nohwnd]

Might be the easiest to just ignore files with .p7s extension. Do you want to send a PR for that change?