Rule checker needs to support specialUse label

## Enhancement Task
Previously, the `specialUse` label was used for auto-scaling TiKV when there was a hotspot. But we indeed have some other requirements, such as we want to put some table's replica to some given stores. The current implementation doesn't support it. See
https://github.com/tikv/pd/blob/7b60e0928d35bbdb1914850040825684853d63f0/pkg/schedule/checker/replica_strategy.go#L64
When creating the filter, we don't add any label to allow the list.
If the checker wants to add a replica to the store with the `specialUse` label, the filter will prevent this thing from happening:
https://github.com/tikv/pd/blob/7b60e0928d35bbdb1914850040825684853d63f0/pkg/schedule/filter/filters.go#L836-L877