chore: add 4.1 upgrade handler

[gsk967]

Signed-off-by: Sai Kumar sai@umee.cc

Description

closes: #1702

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[robert-zaremba]

let's keep "cosmossdk.io/errors" without rename / alias, and sdkerrors "github.com/cosmos/cosmos-sdk/types/errors" as sdkerrors

I have fixed other deprecation warnings in #1788

[robert-zaremba]

pre-approving