Add a link to Markdown documentation in the event creation form

[akatsoulas]

┆Issue is synchronized with this Jira Story

[akatsoulas]

#456

[emilghittasv]

I can confirm that the "Markdown supported" link (which points out to the https://docs.github.com/en/get-started/writing-on-github/getting-started-with-writing-and-formatting-on-github/basic-writing-and-formatting-syntax page) was added inside the "Create an Event" and "Edit Event" forms.

Moving this ticket inside the release column.