use aws role from gh vars

Author: niraj8

.github/workflows/manual-pull.yml

@@ -30,7 +30,7 @@ jobs:
       - name: Configure AWS credentials
         uses: aws-actions/configure-aws-credentials@v4
         with:
-          role-to-assume: arn:aws:iam::222634395437:role/sep-24-meetup-oidc-github
+          role-to-assume: ${{ vars.AWS_ROLE_TO_ASSUME }}
           aws-region: ${{ env.AWS_REGION }}
 
       - name: Update IaC in PR