Do not derive from Singleton in Config (since the object is now in DI).

core/CliMulti/RequestCommand.php

core/Config.php

tests/PHPUnit/Integration/Tracker/ActionTest.php

tests/PHPUnit/Integration/TrackerTest.php

tests/PHPUnit/System/BlobReportLimitingTest.php

tests/PHPUnit/Unit/AssetManagerTest.php

tests/PHPUnit/Unit/Columns/DimensionTest.php

tests/PHPUnit/Unit/DataTable/Filter/PivotByDimensionTest.php

tests/PHPUnit/Unit/DataTable/MapTest.php

tests/PHPUnit/Unit/IPTest.php

tests/PHPUnit/Unit/Plugin/ComponentFactoryTest.php