de-DE weekday/time formats don't match native browser implementation

[romandecker]

Example:

new Intl.DateTimeFormat('de-DE', {weekday: 'short', hour: 'numeric'})
  .format(new Date('2019-08-14T05:36:24.200Z'))

Chrome/Firefox: Mi, 07 Uhr
Intl (@1.2.5): Mi., 7

This is particularly problematic when doing SSR, where we polyfill Intl on the server (to get all locales), but rely on the native browser implementation on the client.