Implement initial version of simulation tests for crosschain functionality

[lumtis]

Describe the Issue
Add messages generation from crosschain and observer modules allowing to simulation CCTX processing in simulation tests.

• Generate vote gas price message for different observers
• Generate vote inbound and outbound messages for observer
• For simplicity we could keep all CCTX of type gas and just simple deposit withdraws and using gas CCTX type
• As v2 will be the only supported interface for protocol contracts, we should just create v2 cctxs

Challenges:

• Need an initial setup with a list of observer
• Need a initial allowing the creation of CCTX with gas
  • Will either need to setup an initial state with preexisting chains and ZRC20s or creating those on the fly in simulation tests Implement chain and ERC20 whitelisting in simulation tests #2974
• Need to vote outbound at some point after inbounds are created
  • We should create the state with pending outbounds and generate vote messages for the different observers
  • Sometime we should also vote for failed outbound (but at a lesser weight)

[kingpinXD]

Added a new issue for the observer module simulation
#3066

[kingpinXD]

Will be creating a separate issue for operations other than
InboundVote and GasPriceVote