Prior to this commit, `ConcurrentReferenceHashMap` subclasses extending `Reference` would call `Reference::clear` right next to `Reference::enqueue`; this is not needed as the latter calls it already. Closes gh-28863
Prior to this commit, `ConcurrentReferenceHashMap` subclasses extending `Reference` would call `Reference::clear` right next to `Reference::enqueue`; this is not needed as the latter calls it already. Closes gh-28863