Disable password autocomplete in mirror form fill
Chrome and other browsers ignore autocomplete=false and
autocomplete=off now. We suspect that this caused the mirroring
section to expand whenever a user clicked "Expand" in the Repository
settings.
https://developers.google.com/web/fundamentals/design-and-ux/input/forms/?hl=en
recommends using new-password as the new field to prevent automatic
filling.
It looks like we already do this in app/views/shared/_field.html.haml.
Edited by Stan Hu