Fix garbage collection about t.droppedSeries in QueueManager.SeriesReset. (#8387)
Fix garbage collection about t.droppedSeries in QueueManager.SeriesReset. (#8387)

* Fix memory leak about t.droppedSeries in QueueManager.SeriesReset.

Signed-off-by: kevinForMyself <d86a423e131006d6c1d8147e1998047d428913ad@163.com>

* Fix garbage collection about t.droppedSeries in QueueManager.SeriesReset

Signed-off-by: kevinForMyself <d86a423e131006d6c1d8147e1998047d428913ad@163.com>
prometheus/prometheus,keegancsmith/prometheus,alileza/prometheus,GoogleCloudPlatform/prometheus,alileza/prometheus,keegancsmith/prometheus,prometheus/prometheus,GoogleCloudPlatform/prometheus,GoogleCloudPlatform/prometheus,alileza/prometheus,keegancsmith/prometheus,keegancsmith/prometheus,GoogleCloudPlatform/prometheus,prometheus/prometheus,GoogleCloudPlatform/prometheus,alileza/prometheus,alileza/prometheus,prometheus/prometheus,keegancsmith/prometheus,prometheus/prometheus