Update the launch script

Author: Cédric Belin

run.ps1

@@ -1,4 +1,5 @@
+#!/usr/bin/env pwsh
 Set-StrictMode -Version Latest
-$file = "$PSScriptRoot\lib\cli.js"
+$file = "$PSScriptRoot/lib/cli.js"
 if (Test-Path "$file.map") { & node --enable-source-maps $file @args }
 else { & node $file @args }