PWA helper for browser apps

PWAs for browser apps like chrome/brave/chromium etc get created on the users desktop, but they are pointed to the bin inside of its jail IE `/opt/brave/brave-browser` it will never work out of the box I suspect, but we can include helper logic to modify the desktop entries with a script to call the proot wrapper instead of the hard coded bin. 

IE `proot-apps fixpwa /path/to/pwa.desktop`