Write Drupal 8 tests for the Drupal 7 User module security issue from SA-CORE-2016-002

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Still needs work for #10

Adding Reroll for 10.1.x.
please review

Still needs a reoll

Also please please add an interdiff or we shouldn't use the patch as we don't what was changed easily.

Fixed failed commands on #21
Attached patch against Drupal 10.1.x
Attached interdiff