External Libraries: zxcvbn library.

This reverts [44354] for more investigation into inconsistent password strength values that passed locally prior to commit.

Unprops omarreiss, netweb, desrosj.
See #43749.
Built from https://develop.svn.wordpress.org/trunk@44356


git-svn-id: https://core.svn.wordpress.org/trunk@44186 1a063a9b-81f0-0310-95a4-ce76da25c4cd