Fix for ShardIDFromKey

[Frozen]

#4564

[sophoah]

@Frozen i think that one is good. Can you add two tests dealing with a network that has HIP30 epoch defined as TBD, and another one set with a fixed number. First one should use the default / genesis sharding config while the other one should use the sharding config of HIP30.

Things to note, at the end what we want is to know the latest sharding configuration (4 shard vs 2 shards) when we start the node from height 0, be it with HIP30 or with future HIP, so maybe we could define a function that does just that.

@diego1q2w @GheisMohammadi feel free to chime in any other ideas.