Allow users to delete releases from edit page

What does this MR do and why?

This is a long-available feature via the graphql API, but we hadn't added the functionality in the UI. It has a small confirmation check before deleting the release, and always navigates the user back to the project's releases page.

Changelog: added

Screenshots or screen recordings

How to set up and validate locally

1. navigate to deployments > releases
2. make a release
3. edit the release
4. select Delete

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

for #213862 (closed)