add github token

Author: zhongkechen

.github/workflows/update-milestone-badge.yml

@@ -23,7 +23,7 @@ jobs:
 
       - name: Fetch nearest milestone and generate badge
         env:
-          GH_TOKEN: ${{ github.token }}
+          GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         run: |
           # Get the nearest open milestone sorted by due date
           MILESTONE=$(gh api repos/${{ github.repository }}/milestones \