Change work item type from quick action
### Release notes
With this additional [quick action](https://docs.gitlab.com/ee/user/project/quick_actions.html#quick-actions-for-issues-and-merge-requests), users can now convert tasks to issues and key results to objectives.

## Problem to solve
Users should be able to change the type of a work item from either an action on the detail view, or a quick action providing similar functionality.
## Proposal
Create a single "change type" [quick action](https://docs.gitlab.com/ee/user/project/quick_actions.html) that reveals the available types. When changing types results in a secondary confirmation (e.g. where data might be destroyed), show the confirmation in the same format as if changing types from outside the quick action.
Potential quick action terminology:
`/type <type>`
issue