8 files declare their use of Counter in Purge 8.3

CapacityTracker.php in src/Plugin/Purge/Purger/CapacityTracker.php

CounterTest.php in tests/src/Unit/Counter/CounterTest.php

NumberOfItemsStatistic.php in src/Plugin/Purge/Queue/NumberOfItemsStatistic.php

RuntimeMeasurement.php in src/Plugin/Purge/Purger/RuntimeMeasurement.php

TotalFailedStatistic.php in src/Plugin/Purge/Queue/TotalFailedStatistic.php

TotalNotSupportedStatistic.php in src/Plugin/Purge/Queue/TotalNotSupportedStatistic.php

TotalProcessingStatistic.php in src/Plugin/Purge/Queue/TotalProcessingStatistic.php

TotalSucceededStatistic.php in src/Plugin/Purge/Queue/TotalSucceededStatistic.php