test: bring back Marshalling/unmarshalling of a wrapped tx test (#10044)

## Description

We still use wrapped transactions so we should test marshaling.

---

### Author Checklist

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I have...

- [ ] included the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] added `!` to the type prefix if API or client breaking change
- [ ] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
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- [ ] followed the guidelines for [building modules](https://github.com/cosmos/cosmos-sdk/blob/master/docs/building-modules)
- [ ] included the necessary unit and integration [tests](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#testing)
- [ ] added a changelog entry to `CHANGELOG.md`
- [ ] included comments for [documenting Go code](https://blog.golang.org/godoc)
- [ ] updated the relevant documentation or specification
- [ ] reviewed "Files changed" and left comments if necessary
- [ ] confirmed all CI checks have passed

### Reviewers Checklist

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your handle next to the items reviewed if you only reviewed selected items.*

I have...

- [ ] confirmed the correct [type prefix](https://github.com/commitizen/conventional-commit-types/blob/v3.0.0/index.json) in the PR title
- [ ] confirmed `!` in the type prefix if API or client breaking change
- [ ] confirmed all author checklist items have been addressed 
- [ ] reviewed state machine logic
- [ ] reviewed API design and naming
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- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

codec/amino_codec_test.go

@@ -11,6 +11,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/codec/types"
 	"github.com/cosmos/cosmos-sdk/simapp"
 	"github.com/cosmos/cosmos-sdk/testutil/testdata"
+	"github.com/cosmos/cosmos-sdk/x/auth/client/cli"
 	"github.com/cosmos/cosmos-sdk/x/auth/migrations/legacytx"
 )
 
@@ -129,4 +130,12 @@ func TestAminoCodecFullDecodeAndEncode(t *testing.T) {
 	marshaledTx, err := legacyCdc.MarshalJSON(tx)
 	require.NoError(t, err)
 	require.Equal(t, string(marshaledTx), txSigned)
+
+	// Marshalling/unmarshalling the tx wrapped in a struct should work.
+	txRequest := &cli.BroadcastReq{
+		Mode: "block",
+		Tx:   tx,
+	}
+	_, err = legacyCdc.MarshalJSON(txRequest)
+	require.NoError(t, err)
 }