Create new user group for WMDE staff at wikidatawiki

This change adds a new user group for WMDE staff
as requested in the bug.
Redundant or for wikidatawiki unnecessary user rights
were left out.

Bug: 72459
Change-Id: I53055588ab164ed74cf63fc0bb1de6c10a7b149e
Merge "Create new user group for WMDE staff at wikidatawiki"