Escaping double quotes

I include the last commit message in my messaging, which works great until I recently did a revert and discovered that commit messages with double quotes break the action.

      - name: Deploy Complete Success Notification
        uses: slackapi/slack-github-action@v2.1.0
        if: success()
        env:
          MESSAGE: "${{ github.event.workflow_run.head_commit.message || github.event.head_commit.message }}"
        with:
          method: chat.postMessage
          token: ${{ secrets.SLACK_NOTIFICATIONS_BOT_TOKEN }}
          payload: |
            channel: monitoring
            text: "FRONTEND: Deployment of '${{ env.MESSAGE }}' to ${{ github.ref_name }} Completed"

I've tried wrapping env.MESSAGE in toJSON (as mentioned as a solution in https://github.com/slackapi/slack-github-action/issues/202), but that does not address the issue with double quotes it seems. I'm also not seeing any suggestions for how to overcome in https://tools.slack.dev/slack-github-action/sending-variables. What is the proper way to get this working correctly?

Reproduce the workflow with a commit message containing double quotes, then review the workaround discussed in issue 202 and the sending-variables documentation linked in the report. The issue is resolved when the deployment notification posts the complete commit message without breaking the action payload.