fix: revert \#10169 (amino multisig key unmarshalling) (#10193)

* Revert "fix: unmarshalling issue with multisig keys in master (backport #10061) (#10169)"

This reverts commit fcaff72.

* Update CHANGELOG.md

Co-authored-by: Amaury <1293565+amaurym@users.noreply.github.com>

Co-authored-by: Amaury <1293565+amaurym@users.noreply.github.com>

CHANGELOG.md

@@ -48,7 +48,6 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 * [\#9969](https://github.com/cosmos/cosmos-sdk/pull/9969) fix: use keyring in config for add-genesis-account cmd.
 * (x/genutil) [#10104](https://github.com/cosmos/cosmos-sdk/pull/10104) Ensure the `init` command reads the `--home` flag value correctly.
-* [\#10061](https://github.com/cosmos/cosmos-sdk/pull/10061) Ensure that `LegacyAminoPubKey` struct correctly unmarshals from JSON
 * (x/feegrant) [\#10049](https://github.com/cosmos/cosmos-sdk/issues/10049) Fixed the error message when `period` or `period-limit` flag is not set on a feegrant grant transaction.
 
 ### Client Breaking Changes

crypto/keys/multisig/amino.go

@@ -78,9 +78,7 @@ func (m *LegacyAminoPubKey) UnmarshalAminoJSON(tmPk tmMultisig) error {
 	// Instead of just doing `*m = *protoPk`, we prefer to modify in-place the
 	// existing Anys inside `m` (instead of allocating new Anys), as so not to
 	// break the `.compat` fields in the existing Anys.
-	m.PubKeys = make([]*types.Any, len(protoPk.PubKeys))
 	for i := range m.PubKeys {
-		m.PubKeys[i] = &types.Any{}
 		m.PubKeys[i].TypeUrl = protoPk.PubKeys[i].TypeUrl
 		m.PubKeys[i].Value = protoPk.PubKeys[i].Value
 	}

crypto/keys/multisig/multisig_test.go

@@ -428,14 +428,6 @@ func TestAminoUnmarshalJSON(t *testing.T) {
 	require.NoError(t, err)
 	lpk := pk.(*kmultisig.LegacyAminoPubKey)
 	require.Equal(t, uint32(3), lpk.Threshold)
-	require.Equal(t, 5, len(pk.(*kmultisig.LegacyAminoPubKey).PubKeys))
-
-	for _, key := range pk.(*kmultisig.LegacyAminoPubKey).PubKeys {
-		require.NotNil(t, key)
-		pk := secp256k1.PubKey{}
-		err := pk.Unmarshal(key.Value)
-		require.NoError(t, err)
-	}
 }
 
 func TestProtoMarshalJSON(t *testing.T) {