Use Jira Expressions

[dspasojevic]

Evaluate the use of Jira Expressions instead of the current approach to fetch the data.

v3 of the plain REST APIs store descriptions as structured JSON objects instead of wikitext, so eventually a different approach (like Jira Expressions) will be necessary.

[lfzolati]

@dspasojevic, should I be added as an assignee for this issue? Also can I clarify what you mean by evaluate - what are your acceptance criteria for this issue? Cheers.