Backup Management: Delete option

User story:
As a PMM user, I need to be able to delete artifact from the storage, so it's not occupying the space on the  storage  

UI/UX:
https://www.figma.com/file/Fk9p1JX7sYAOzBjoR9u8WU/Backup-Management?node-id=426%3A1331

Acceptance criteria

• Confirmation modal window with confirmation info and The "Delete from Storage" checkbox appears on clicking Delete button\icon for selected artifact
• The "Delete from Storage" checkbox is selected by default
• If the "Delete from Storage" checkbox is selected, then the artifact is also deleted from Storage; otherwise, delete from artifacts list only
• Documentation updated about deletion 
• Disallow artifact removal if artifact is not in the final state e.g. backup is currently being created (status In progress).
• Disallow artifact removal if backup is being used by any restore operation that is In progress.

Out of scope:

• Bulk actions

Suggested implementation:
On the FE side add a "Delete" button on each artifact entry clicking on it will open confirmation modal window with checkbox "Delete from Storage".

On the BE side implement an endpoint /v1/management/backup/Artifacts/Delete with option to delete actual backup files from s3 storage. Remove all the restore history items that is associated with the artifact.