Backend

* Add the branch name to Jira comments.
* If `comment_detail` is set to `all_details`, include more information like commit SHA / MR number and full commit message as described in https://gitlab.com/gitlab-org/gitlab/-/issues/195887#comment-types-examples.
* Add some simple specs and update existing ones.

Frontend

* Expand the Vue component to include the Jira trigger fields.
* Add wrapping component `IntegrationForm`.
* Add `JiraTriggerFields` which shows/hides sections based on user selection.
* Use translations