reenable test

reenabled it because the test should pass now
9 jobs for 26-checkuserexistance-error-if-user-does-not-exist in 2 minutes and 47 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Lint
passed #2831
lint:lint-php5.4

00:00:37

passed #2832
lint:lint-php5.6

00:00:36

passed #2833
lint:lint-php7.0

00:00:36

passed #2834
lint:lint-php7.1

00:00:25

 
  Codesniffer
passed #2835
codesniffer

00:00:32

 
  Unit
passed #2836
unit:testBasic

00:00:41

passed #2837
unit:testRead

00:00:42

passed #2838
unit:testReadAssertFail

00:00:29

passed #2839
unit:testUserProperty

00:00:44