Add GitHub Copilot instructions for AL development workflow#29180

Copilot wants to merge 1 commit intomainmicrosoft/ALAppExtensions:mainfrom

copilot/fix-ce715f44-e53a-48f2-928e-805594761475microsoft/ALAppExtensions:copilot/fix-ce715f44-e53a-48f2-928e-805594761475Copy head branch name to clipboard