Create function to download assigned Jira tickets to org mode file

[gbastkowski]

Description

Create a function that downloads Jira tickets assigned to me and saves them in an org mode file with correct syntax.

Eventually I want to be able to use org clock-in so that I for example can figure out the current issue number automatically and insert it quickly as prefix or branch name with magit.

Acceptance Criteria

• Function connects to Jira API
• Fetches tickets assigned to user
• Converts ticket data to org mode format
• Saves to hardcoded file location
• Overwrites file on each execution