Convert the line breaks to Slack \n

[denis-trofimov]

Then I pass output of Run LoveToKnow/slackify-markdown-action@v1.0.0 to the slackapi/slack-github-action@v1.24.0, I can have error "passed in payload was invalid JSON".

I think Slack is breaking on '%0A', expecting text "\n".

Line breaks
You can use multi-line text in app-generated text. Insert a newline by including the string \n in your text. For example:
This is a line of text.\nAnd this is another one.

Example text input should be any line break containing.

##[debug]..Evaluating String:
##[debug]..=> 'message'
##[debug]=> '**Your Huma server API is ready to use.✅**
##[debug]
##[debug]Huma server API links:
##[debug]

::set-output name=text::​*Your Huma server API is ready to use.✅*​%0A%0AHuma server API links:%0A

My part of Github workflow:

    - id: convertTextSlackReady
      if: steps.install.outputs.error == 0 &&  steps.restore.outputs.error == 0
      uses: LoveToKnow/slackify-markdown-action@v1.0.0
      with:
        text: ${{ steps.readyMessage.outputs.message }}

    - name: Slack links list
      if: steps.install.outputs.error == 0 &&  steps.restore.outputs.error == 0
      uses: slackapi/slack-github-action@v1.24.0
      with:
        channel-id: ${{ inputs.slack_channel_id }}
        payload: |
          {
            "text": "Your server API is ready to use.",
            "blocks": [
              {
                "type": "section",
                "text": {
                  "type": "mrkdwn",
                  "text": "${{ steps.convertTextSlackReady.outputs.text }}"
                }
              }
            ]
          }
      env:
        SLACK_BOT_TOKEN: ${{ inputs.slack_bot_token }}