fix: warning message duplicate

[cchanche]

Steps to reproduce

• Create simple pull_request workflow file :

# .github/workflows/pr-description.yml
name: Set PR description
on:
  pull_request:
    types: [opened, synchronize, edited, reopened, ready_for_review]

jobs:
  update-pr-body:
    name: 💬 Jira details
    runs-on: ubuntu-20.04
    steps:
      - uses: actions/checkout@v3

      - uses: cakeinpanic/[email protected]
        with:
          github-token: ${{ secrets.GITHUB_TOKEN }}
          jira-token: ${{ secrets.JIRA_TOKEN }}
          jira-base-url: [your jira base URL]
          jira-project-key: [your jira project key]
          use: both

• Open a pull-request containing this file
• Wait until the workflow finishes, you should see the following description :

<!--do not remove this marker, its needed to replace info when ticket title is updated -->
<!--jira-description-action-hidden-marker-start-->

<table>
...
</table>
<br />

<!--jira-description-action-hidden-marker-end-->

• Go to to the latest workflow run in the Actions tab, and click "Re-run all jobs
• Wait until the workflow finishes, you should see the following description :

<!--do not remove this marker, its needed to replace info when ticket title is updated -->
<!--jira-description-action-hidden-marker-start-->

<table>
...
</table>
<br />

<!--jira-description-action-hidden-marker-end-->
<!--do not remove this marker, its needed to replace info when ticket title is updated -->

The WARNING_MESSAGE_ABOUT_HIDDEN_MARKERS is being stacked on each update.