Accessibility: Script Loader: Remove jQuery as dependency of `admin-bar` after [46440].

A better approach needs to be explored, as there are valid concerns for potential conflicts between different jQuery versions added by themes or plugins.

See #47069.

Built from https://develop.svn.wordpress.org/trunk@46550


git-svn-id: https://core.svn.wordpress.org/trunk@46347 1a063a9b-81f0-0310-95a4-ce76da25c4cd