* Aura: Report malice on sibling blocks from the same validator
This was originally written by @vkomenda, then squashed for
easier rebasing on master. Cleanup of `received_step_hashes`
was moved to `verify_block_family`, since `on_prepare_block`
does not exist on master, and a unit test was added.
Original commit messages:
added the map of received block header hashes
do not return an error and remove older received block records
optimised older record removal
block hash comparison optimisation and the weak client ref fix
SIBLING_MALICE_DETECTION_PERIOD constant
review comments
using step numbers instead of block numbers
* Add docs; use map_or.
* Update step hash record comment.
Co-Authored-By: David <dvdplm@gmail.com>
* Remove hash records after 2 rounds instead of 100 steps.
f59ed47b1b