Create Release Prep MR generating script

Our release process is a giant checklist living in a gitlab template which, while nice and organized and cool, could be partially automated. The things we've enumerated include:

• translation hash updates
• rbm.conf
  • version
  • incrementals
  • release date
• dependency checking and config updating for:
  • noscript
  • ublock
  • mullvad extension
  • openssl
  • zlib
  • zstd
  • tor
  • go
  • manual
  • tor-browser
  • geckoview
  • firefox-android
• improved changelog generation (eg include esr/geckoview updates, etc)
  • handle updates when passed manually to the script
  • wire the script to the release preparation script and automate it even more!
• qa + release emails
• website MR
• blog MR