Dymint migrates the keyring of settlement hub

[mtsitrin]

The keyring has been refactored in v0.46 (https://github.com/cosmos/cosmos-sdk/blob/main/UPGRADING.md#keyring)

As dymint uses hub's keyring it automatically migrates it

If dymint uses cosmos sdk v0.46, it corrupts the keyring of the hub (as it's still in v0.45.x)

Before running dymint

 ~/Applications/dymension/RDK/dymint  #v0.2.2-alpha !3 ?1  dymd keys list $KRB                                                                                                                                 
- name: local-user
  type: local
  address: dym1alycrxds265v8dq6jrsgmw45fvpp3vnaywsy42
  pubkey: '{"@type":"/cosmos.crypto.secp256k1.PubKey","key":"AhIWJdNwWc8qn3QIbuXhJnFodWK82upQUuoAJpElPUJ2"}'
  mnemonic: ""

When running dymint in version v0.46.6

Successfully migrated key local-user.info.

After:

dymd keys list $KRB                                                                                                                                 
Error: Bytes left over in UnmarshalBinaryLengthPrefixed, should read 10 more bytes but have 157

Maybe dymint should copy somehow the keyring from settlement instead of upgrading it's version? otherwise we'll have version coupling between rollapp and hub

or upgrade the hub to v0.46.x