Invoke-Item.Tests.ps1 should handle finding multiple ping executables

[JamesWTruher]

On openSUSE the following test failed for Beta.9.

message     : Expected: {Invoke-Item : Cannot find path '/usr/bin/ping /bin/ping' because it does not
              exist.
              At line:1 char:1
              + Invoke-Item '/usr/bin/ping /bin/ping'
              + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
                  + CategoryInfo          : ObjectNotFound: (/usr/bin/ping /bin/ping:String)
                  [Invoke-Item], ItemNotFoundException
                  + FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.Invok
                 eItemCommand

              } to match the expression {usage: ping}
stack-trace : at line: 77 in /TEST/PowerShell/test/powershell/Modules/Microsoft.PowerShell.Utility/Invoke-Item.Tests.ps1
              77:             Get-Content $redirectFile -Raw | Should Match "usage: ping"

The test should handle finding multiple copies of ping

[kalgiz]

Fixed in #6120