GitHub Desktop 3.5.12-beta1

Fixed

• Fix launching custom shells - #22186
• Fix crash trying to run a non-existent script - #22167
• Restore keyboard focus to the commit button after the commit progress dialog closes - #22192

Added

• Add model selection for Copilot - #21745
• Add support for custom model providers for Copilot - #22000
• Use repo rules to guide commit messages generation by Copilot - #22007