Modify the issue association flow and Issue display

[sergeibbb]

Description

part of #4332

• move the issue card above the branch card
• when no issue is associated, display an element with "Current work item" on the left and the issue icon to the right.
• when the issue icon is hovered, display a tooltip with "Associate an issue"
• when the issue icon is clicked, open the issue association flow

• when an issue is associated, display the issue card
• modify the current issue card to be shorter than the other cards (reduce the top/bottom padding to 4px from 8px)

Checklist

• I have followed the guidelines in the Contributing document
• My changes follow the coding style of this project
• My changes build without any errors or warnings
• My changes have been formatted and linted
• My changes include any required corresponding changes to the documentation (including CHANGELOG.md and README.md)
• My changes have been rebased and squashed to the minimal number (typically 1) of relevant commits
• My changes have a descriptive commit message with a short title, including a Fixes $XXX - or Closes #XXX - prefix to auto-close the issue that your PR addresses

[sergeibbb]

@d13

I've updated the PR. The old version modified issues in recent branches as well as in the current one. Now it's fixed.

[d13]

LGTM, just needs a conflict resolution