[SDK Unfork] switch fork to cosmossdk.io/math

[p0mvn]

Background

Prior to being able to replace all usage of sdk.Dec and sdk.Int with respective sdkmath types in Osmosis, we need to make sure that our fork is updated.

Suggested Design

Follow history: https://github.com/cosmos/cosmos-sdk/commits/main?after=09db6997c532e984905b33f8618b57b2bbd1fed1+34&branch=main&path%5B%5D=math&qualified_name=refs%2Fheads%2Fmain

1. Create type alias for Int and Uint, delete in-repo implementations, ref: refactor!: create math go sub module cosmos/cosmos-sdk#11788
2. Create type alias for Dec, delete in -repo implementations, ref: refactor: Move sdk.Dec to math package cosmos/cosmos-sdk#12634

Acceptance Criteria

• fork is fully switched to sdkmath