Allows author to vote on their own issue

What does this MR do?

Allows author to vote on their own issue.

What are the relevant issue numbers?

#43283 (closed) - Upvote and downvote issues/merge requests/epics/comments you've created

Screenshots

User can upvote/downvote to their own issues/MRs

User can upvote/downvote to their own comments/discussions

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides