Install GitHub CLI on Windows images (#853)

* Install GitHub CLI on Windows images

* Resolve comments

Co-authored-by: Sergey Dolin <v-sedoli@micorosoft.com>

images/win/scripts/Installers/Validate-GitHub-CLI.ps1

@@ -0,0 +1,27 @@
+################################################################################
+##  File:  Validate-GitHub-CLI.ps1
+##  Desc:  Validate GitHub CLI
+################################################################################
+
+$command = Get-Command -Name 'gh'
+
+if ($command)
+{
+    Write-Host "gh on path"
+}
+else
+{
+    Write-Host 'gh is not on path'
+    exit 1
+}
+
+# Adding description of the software to Markdown
+$SoftwareName = "GitHub CLI"
+
+$version = (gh --version).Split()[2]
+
+$Description = @"
+_Version:_ $version<br/>
+"@
+
+Add-SoftwareDetailsToMarkdown -SoftwareName $SoftwareName -DescriptionMarkdown $Description