The actions-rs helpers spew out a bunch of warnings about using deprecated features that are going away soon. They also aren't any faster than the old manual way of doing things which worked fine.
The old way would just always use the cached corpus from the first run then never update the cache. If I understand this restore-keys configuration, then this should change the behavior to always update the corpus used in this latest run then try to restore from the most recent run the next time around.