The old one was wrong in two ways: the first block in chain.rlp was the
genesis block, and the genesis difficulty was below minimum difficulty.
This also contains some other fixes to the test.
This adds a test suite for discovery v4. The test suite is a port of the Hive suite for
discovery, and will replace the current suite on Hive soon-ish. The tests can be
run locally with this command:
devp2p discv4 test -remote enode//...
Co-authored-by: Felix Lange <fjl@twurst.com>