This function allows for faster insertions into tombstone-heavy
probe sequences by short-circuiting on tombstones rather than
continuing to probe. The user must already guarantee that the
entry being inserted is unique. If a non-unique key is inserted
with this operation, undefined behavior will result.
This operation moves ownership from one hash set object
to another and re-assigns callback functions to developer-specified
values. This allows for dynamic configuration of allocation
callbacks and is necessary for use-cases involving executable code
which may be unmapped underneath the hash set.
The developer is responsible for enforcing barriers and enforcing
the visibility of the new hash set.