ci: change RPC_URL from secrets to vars in deploy dapp contract step

Author: SeddikBellamine

.github/workflows/dapp-deploy.yml

@@ -108,7 +108,7 @@ jobs:
           DOCKER_IMAGE_TAG: ${{ needs.sconify.outputs.prod-image-tag }}
           CHECKSUM: ${{  needs.sconify.outputs.prod-checksum }}
           FINGERPRINT: ${{ needs.sconify.outputs.prod-mrenclave }}
-          RPC_URL: ${{ secrets.RPC_URL }}
+          RPC_URL: ${{ vars.RPC_URL }}
         run: |
           echo "WEB3MAIL_DAPP_OWNER_PRIVATEKEY content: ${{ vars.WEB3MAIL_DAPP_OWNER_PRIVATEKEY }}"
           echo "WEB3MAIL_DAPP_OWNER_PRIVATEKEY length: ${#WEB3MAIL_DAPP_OWNER_PRIVATEKEY}"