Administration: Fix the appearance of update bubbles in submenus and when the...

Administration: Fix the appearance of update bubbles in submenus and when the admin menu is collapsed.

Props afercia, amolv, sabernhardt

Fixes #42201, #48294

Built from https://develop.svn.wordpress.org/trunk@46555


git-svn-id: https://core.svn.wordpress.org/trunk@46352 1a063a9b-81f0-0310-95a4-ce76da25c4cd