As a Jira user I'd like to have the Jira Data Center for Slack plugin sending messages with the Markdown format

Issue Summary

Notifications in Slack are not rendered as per Jira's text formatting, and as a Jira user, I'd like to see the messages in Slack without the unsupported and non-parsed characters, This may be done by parsing the Jira Text Formatting Notation to Markdown, compatible with Slack.

Environment

• Jira Software DC 8.22.6, 9.4.9
• Slack
• Jira Data Center for Slack (Official) app

Steps to Reproduce

1. Configure Jira to Slack as per this guide
2. Check the option to send a message to the channel when 'Someone leaves a comment'
3. Add a new comment and observe the message in Slack
4. Add another comment that uses multiple text formatting in Jira. i.e.:

   h1.  +Formmated+ _comment_
   * *_item_*
   *  +item2+
   * {color:red}item3{color}
   

5. Observe the message in Slack

Expected Results

Text formatting is preserved in the Slack message

Actual Results

Not all text formatting is preserved in the Slack message. As a result, messages may be difficult to read in Slack.

Notes

Text formatting for Slack can be found in this link

Since underlining and colors is not supported in Slack's Markdown format, the messages may be difficult to read having additional characters.

Workaround

Currently, there is no known workaround for this behavior. A workaround will be added here when available