Media a11y: Don't set role=checkbox for the attachment details view.

Some unnecessary attributes were inherited from the attachment view, which created difficulties with screen readers.

fixes #30390.

Built from https://develop.svn.wordpress.org/trunk@30483


git-svn-id: http://core.svn.wordpress.org/trunk@30471 1a063a9b-81f0-0310-95a4-ce76da25c4cd