Allow everyone who has rights to edit issue comment also delete attachments

[lafriks]

Currently only user that uploaded attachment can delete it (follow up from #8426)

[sapk]

Related to #7956 (if I have time 😄)

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs during the next 2 weeks. Thank you for your contributions.