As a developer, I want to broadcast block only after they have been fully validated, to avoid broadcasting invalid blocks

[tizoc]

Blocks received from the gossip network are currently being broadcasted without being validated first, this is not correct behavior and may result in the nodes being banned.

The same happens with other gossip messages (snarks and transactions).

Task is to delay re-broadcasting until we know that the data is valid (and to skip broadcasting for invalid data, possibly also banning the peer).

Right now broadcasting happens when processing the incoming message here even before it has been successfully decoded:

https://github.com/openmina/openmina/blob/5baabe6e62ef3637b651b8a974a8cdd93aca4696/p2p/src/network/pubsub/p2p_network_pubsub_reducer.rs#L473-L492
https://github.com/openmina/openmina/blob/5baabe6e62ef3637b651b8a974a8cdd93aca4696/p2p/src/network/pubsub/p2p_network_pubsub_reducer.rs#L187

[tizoc]

A few improvements here, but just to delay broadcasting until we make sure that the message can be decoded #953 plus a little cleanup in #955

[0xMimir]

Mostly added message validation, but discovered that test pubsub_receive_block can't' fail

[0xMimir]

Fixed pubsub_receive_block test so it can fail, delayed block broadcast until block is successfully applied