Optimint + Cosmos SDK v0.46.x

[tzdybal]

• create a branch for Optimint-enabled Cosmos SDK based on v0.46.x
• Update Optimint for v0.46.x compatibility #529
• Release Optimint v0.4.0
• Release/tag Cosmos SDK
• Update instances of Optimint to Rollmint celestiaorg/docs#249

[tzdybal]

cosmos-sdk changes: https://github.com/celestiaorg/cosmos-sdk/compare/v0.46.1...celestiaorg:cosmos-sdk:release/v0.46.x-optimint?expand=1

[tzdybal]

Closing, as last part (docs) only needs review.