Jira issues in GitLab feature should be configurable via the API
### Problem
After releasing the first iteration of the [View Jira issues in GitLab](https://docs.gitlab.com/ee/user/project/integrations/jira.html#view-jira-issues) feature, we have not added the ability to configure this feature using the [API](https://docs.gitlab.com/ee/api/services.html#createedit-jira-service).
### Proposal
- Add this capability to the API
- Update API documentation
issue