UX: Post a comment on the JIRA issue details page
### User story:
_As this developer, I want to be able to view comments and wrote a new comment on the JIRA issue details, so I can participate in discussion of the work._
### Proposal:
1. GitLab user must first authenticate with their Jira account https://gitlab.com/gitlab-org/gitlab/-/issues/300195/
1. Once authenticated, system communicates that their Jira account has been linked and that all their activity will be associated with their Jira account
1. GitLab user has the ability to comment under their Jira account
:pencil2: See mockup of flow:
https://gitlab.com/gitlab-org/gitlab/-/issues/293020/designs/Add-comment-flow.png
issue