Automated tests for markdown2html() with all extensions

[atodorov]

Kiwi TCMS needs additional automated test(s) as mentioned in subject.

The markdown2html() function is used to render Markdown (e.g. TestCase text) into the HTML templates that we use. This function makes use of several markdown extensions which are not enabled by default). Then it also uses bleach to remove any possible unsafe HTML. All of that needs automated tests

Definition of Done:

• All scenarios implemented
• CI pass
• All code review passed & PR merged

Hints:

• Devel getting started docs: https://kiwitcms.readthedocs.io/en/latest/contribution.html#testing
• Django testing documentation: https://docs.djangoproject.com/en/3.0/topics/testing/
• Python unittest documentation: https://docs.python.org/3.7/library/unittest.html

This issue is part of Kiwi TCMS open source bounty program. For more information see the link(s) in bounty-program milestone