added Pester test for mode flags in ls output

src/pester-tests/Test-Get-Item.Tests.ps1

@@ -18,4 +18,8 @@
         (Get-Item /usr/bin) | Should Not BeNullOrEmpty
         (Get-Item ..) | Should Not BeNullOrEmpty
     }
+
+    It "Should have mode flags set" {
+        ls / | foreach-object { $_.Mode | Should Not BeNullOrEmpty }
+    }
 }