Add -Force to Expand-Archive

As noted in the console spew of this test:  https://helix.dot.net/api/2019-06-17/jobs/82bbddae-4a56-4002-b3ee-a8768311a92b/workitems/Microsoft.AspNetCore.SpaServices.Extensions.Tests-netcoreapp3.0/console it's quite possible for Node to be unpacked, but not on the path (generally on a helix machine it's because your parent process was created before the previous guy who unzipped Node and put it on the path ran, so only after reboot would you see the effect you want.

eng/helix/content/InstallNode.ps1

@@ -48,9 +48,10 @@ Write-Host "Extracting to $tempDir"
 
 if (Get-Command -Name 'Microsoft.PowerShell.Archive\Expand-Archive' -ErrorAction Ignore) {
     # Use built-in commands where possible as they are cross-plat compatible
-    Microsoft.PowerShell.Archive\Expand-Archive -Path "nodejs.zip" -DestinationPath $tempDir
+    Microsoft.PowerShell.Archive\Expand-Archive -Path "nodejs.zip" -DestinationPath $tempDir -Force
 }
 else {
+    Remove-Item $tempDir -Recurse -ErrorAction Ignore
     # Fallback to old approach for old installations of PowerShell
     Add-Type -AssemblyName System.IO.Compression.FileSystem
     [System.IO.Compression.ZipFile]::ExtractToDirectory("nodejs.zip", $tempDir)