Remove deprecated Admin user multirole functionality #4741

Job	Run time
Debug	1s
Check files / Changed	14s
XML Syntax	0s
Code-QL	0s
Composer / Validation	10s
PHPStan / Analyze (ubuntu-latest, 8.2)	2m 50s
PHPStan / Analyze (ubuntu-latest, 8.3)	2m 42s
PHP CS Fixer / Validation	1m 25s
PHP CS / Default	4m 4s
PHP CS / Ecg	2m 6s
PHP CS / PhpCompatibility	5m 14s
PHP Syntax	0s
Unit Tests (Sonar)	0s
Unit Tests (OpenMage)	0s
	18m 46s

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