fix:Update approve-merge.yml (#375)

Updates to add a new GH_APPROVER_TOKEN, to fix the workflow.

Author: willum070

.github/workflows/approve-merge.yml

@@ -41,10 +41,10 @@ jobs:
         run: gh pr review --approve "$PR_URL"
         env:
           PR_URL: ${{ github.event.pull_request.html_url }}
-          GH_TOKEN: ${{ secrets.GH_MERGE_TOKEN }}
+          GH_TOKEN: ${{ secrets.GH_APPROVER_TOKEN }}
 
       - name: Merge PR
         run: gh pr merge --auto --squash --delete-branch "$PR_URL"
         env:
           PR_URL: ${{ github.event.pull_request.html_url }}
-          GH_TOKEN: ${{ secrets.GH_MERGE_TOKEN }}
+          GH_TOKEN: ${{ secrets.GH_APPROVER_TOKEN }}