Adding GHA permission for GitHub Packages

When a tap stores bottles in GitHub Packages, then the publish workflow requires the corresponding write permission.

Library/Homebrew/dev-cmd/tap-new.rb

@@ -114,6 +114,7 @@ module Homebrew
           runs-on: ubuntu-22.04
           permissions:
             contents: write
+            packages: #{args.github_packages ? "write" : "none"}
             pull-requests: write
           steps:
             - name: Set up Homebrew