Add a TxBody to Conway

[Soupstraw]

This PR adds the ConwayTxBody data type. It deprecates protocol parameter updates and mir certificates, and adds sequences of governance actions and votes to the transaction body.

I added new data types Vote and GovernanceActionInfo, which store information about votes and governance actions respectively.

The currently supported governance actions are:

• parameter change
• hard fork initiation
• treasury withdrawals

I also implemented ToCBOR and FromCBOR instances for all the new data types and created a new CDDL file for Conway era.

Some of the Conway tests were disabled for now until we get the rules sorted out. I added TODO comments in those places.

resolves #3145
resolves #3154

[lehins]

@Soupstraw FYI, checkout recent changes to TxBodyRaw and TxBody field naming. We want to keep it consistent going forward.

https://github.com/input-output-hk/cardano-ledger/blob/50addb0a3d4ab1163f7fac116623d5c29053a7f7/eras/babbage/impl/src/Cardano/Ledger/Babbage/TxBody.hs#L193-L213

and

https://github.com/input-output-hk/cardano-ledger/blob/50addb0a3d4ab1163f7fac116623d5c29053a7f7/eras/babbage/impl/src/Cardano/Ledger/Babbage/TxBody.hs#L533-L550

[teodanciu]

There's a few undefined in the code, did you want to merge them like this @Soupstraw ?

[Soupstraw]

Oh I thought I handled all of them. Let me check

[lehins]

Here is some more feedback, besides what @teodanciu already pointed about a bunch if undefined.

[JaredCorduan]

this is awesome work @Soupstraw , thank you! I made a few small comments.