chore: tips cli audit changes (#11632)

## Description

Closes: #11087 



---

### Author Checklist

*All items are required. Please add a note to the item if the item is not applicable and
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

*All items are required. Please add a note if the item is not applicable and please add
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)

client/tx/tx.go

@@ -361,14 +361,10 @@ func makeAuxSignerData(clientCtx client.Context, f Factory, msgs ...sdk.Msg) (tx
 	}
 
 	if f.tip != nil {
-		if f.tip.Tipper == "" {
-			return tx.AuxSignerData{}, sdkerrors.Wrap(errors.New("tipper flag required"), "tipper")
-		} else {
-			if _, err := sdk.AccAddressFromBech32(f.tip.Tipper); err != nil {
-				return tx.AuxSignerData{}, sdkerrors.ErrInvalidAddress.Wrap("tipper must be a bech32 address")
-			}
-			b.SetTip(f.tip)
+		if _, err := sdk.AccAddressFromBech32(f.tip.Tipper); err != nil {
+			return tx.AuxSignerData{}, sdkerrors.ErrInvalidAddress.Wrap("tipper must be a bech32 address")
 		}
+		b.SetTip(f.tip)
 	}
 
 	err = b.SetSignMode(f.SignMode())

x/auth/client/testutil/suite.go

@@ -1596,24 +1596,6 @@ func (s *IntegrationTestSuite) TestAuxToFee() {
 		tipperArgs         []string
 		feePayerArgs       []string
 	}{
-		{
-			name:     "when --aux and --sign-mode = direct set: error",
-			tipper:   tipper,
-			feePayer: feePayer,
-			tip:      tip,
-			tipperArgs: []string{
-				fmt.Sprintf("--%s=%s", flags.FlagSignMode, flags.SignModeDirect),
-				fmt.Sprintf("--%s=%s", flags.FlagTip, tip),
-				fmt.Sprintf("--%s=true", flags.FlagAux),
-			},
-			expectErrAux: true,
-			feePayerArgs: []string{
-				fmt.Sprintf("--%s=true", flags.FlagSkipConfirmation),
-				fmt.Sprintf("--%s=%s", flags.FlagBroadcastMode, flags.BroadcastSync),
-				fmt.Sprintf("--%s=%s", flags.FlagFrom, feePayer),
-				fmt.Sprintf("--%s=%s", flags.FlagFees, fee.String()),
-			},
-		},
 		{
 			name:     "when --aux and --sign-mode = direct set: error",
 			tipper:   tipper,