fix: multisig works with only multisig name as argument, not its address (#11197)

## Description

Closes: #11196 
ref: https://github.com/terra-money/core/issues/570

multisig flag now works with both address and name as arguments for signing

---

### Author Checklist

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please add links to any relevant follow up issues.*

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))
- [ ] provided a link to the relevant issue or specification
- [ ] 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
- [ ] reviewed documentation is accurate
- [ ] reviewed tests and test coverage
- [ ] manually tested (if applicable)

x/auth/client/cli/tx_sign.go

@@ -9,6 +9,7 @@ import (
 	"github.com/cosmos/cosmos-sdk/client"
 	"github.com/cosmos/cosmos-sdk/client/flags"
 	"github.com/cosmos/cosmos-sdk/client/tx"
+	sdk "github.com/cosmos/cosmos-sdk/types"
 	authclient "github.com/cosmos/cosmos-sdk/x/auth/client"
 )
 
@@ -241,9 +242,13 @@ func makeSignCmd() func(cmd *cobra.Command, args []string) error {
 
 		overwrite, _ := f.GetBool(flagOverwrite)
 		if multisig != "" {
-			multisigAddr, _, _, err := client.GetFromFields(txFactory.Keybase(), multisig, clientCtx.GenerateOnly)
+			multisigAddr, err := sdk.AccAddressFromBech32(multisig)
 			if err != nil {
-				return fmt.Errorf("error getting account from keybase: %w", err)
+				// Bech32 decode error, maybe it's a name, we try to fetch from keyring
+				multisigAddr, _, _, err = client.GetFromFields(txFactory.Keybase(), multisig, clientCtx.GenerateOnly)
+				if err != nil {
+					return fmt.Errorf("error getting account from keybase: %w", err)
+				}
 			}
 			err = authclient.SignTxWithSignerAddress(
 				txF, clientCtx, multisigAddr, fromName, txBuilder, clientCtx.Offline, overwrite)