fix: fixed missing coin denomination in msg server logs (cosmos#9786)

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## Description

Closes: [cosmos#9785](cosmos#9785)

This PR modifies _x/staking/keeper/msg_server.go_ file and fixes coin denomination issues in the emitted events.


---

### 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...

- [x] 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
- [x] targeted the correct branch (see [PR Targeting](https://github.com/cosmos/cosmos-sdk/blob/master/CONTRIBUTING.md#pr-targeting))
- [x] provided a link to the relevant issue or specification
- [x] 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
- [x] 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...

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

CHANGELOG.md

@@ -69,7 +69,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 
 * [\#9594](https://github.com/cosmos/cosmos-sdk/pull/9594) Remove legacy REST API. Please see the [REST Endpoints Migration guide](https://docs.cosmos.network/master/migrations/rest.html) to migrate to the new REST endpoints.
 * [\#9781](https://github.com/cosmos/cosmos-sdk/pull/9781) Improve`withdraw-all-rewards` UX when broadcast mode `async` or `async` is used.
-
+* [\#9785](https://github.com/cosmos/cosmos-sdk/issues/9785) Missing coin denomination in logs 
 
 ### CLI Breaking Changes
 

x/staking/client/testutil/suite.go

@@ -212,6 +212,15 @@ func (s *IntegrationTestSuite) TestNewCreateValidatorCmd() {
 				txResp := tc.respType.(*sdk.TxResponse)
 				require.Equal(tc.expectedCode, txResp.Code,
 					"test: %s, output\n:", tc.name, out.String())
+
+				events := txResp.Logs[0].GetEvents()
+				for i := 0; i < len(events); i++ {
+					if events[i].GetType() == "create_validator" {
+						attributes := events[i].GetAttributes()
+						require.Equal(attributes[1].Value, "100stake")
+						break
+					}
+				}
 			}
 		})
 	}

x/staking/keeper/msg_server.go

@@ -112,7 +112,7 @@ func (k msgServer) CreateValidator(goCtx context.Context, msg *types.MsgCreateVa
 		sdk.NewEvent(
 			types.EventTypeCreateValidator,
 			sdk.NewAttribute(types.AttributeKeyValidator, msg.ValidatorAddress),
-			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Value.Amount.String()),
+			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Value.String()),
 		),
 		sdk.NewEvent(
 			sdk.EventTypeMessage,
@@ -235,7 +235,7 @@ func (k msgServer) Delegate(goCtx context.Context, msg *types.MsgDelegate) (*typ
 		sdk.NewEvent(
 			types.EventTypeDelegate,
 			sdk.NewAttribute(types.AttributeKeyValidator, msg.ValidatorAddress),
-			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Amount.Amount.String()),
+			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Amount.String()),
 			sdk.NewAttribute(types.AttributeKeyNewShares, newShares.String()),
 		),
 		sdk.NewEvent(
@@ -301,7 +301,7 @@ func (k msgServer) BeginRedelegate(goCtx context.Context, msg *types.MsgBeginRed
 			types.EventTypeRedelegate,
 			sdk.NewAttribute(types.AttributeKeySrcValidator, msg.ValidatorSrcAddress),
 			sdk.NewAttribute(types.AttributeKeyDstValidator, msg.ValidatorDstAddress),
-			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Amount.Amount.String()),
+			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Amount.String()),
 			sdk.NewAttribute(types.AttributeKeyCompletionTime, completionTime.Format(time.RFC3339)),
 		),
 		sdk.NewEvent(
@@ -362,7 +362,7 @@ func (k msgServer) Undelegate(goCtx context.Context, msg *types.MsgUndelegate) (
 		sdk.NewEvent(
 			types.EventTypeUnbond,
 			sdk.NewAttribute(types.AttributeKeyValidator, msg.ValidatorAddress),
-			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Amount.Amount.String()),
+			sdk.NewAttribute(sdk.AttributeKeyAmount, msg.Amount.String()),
 			sdk.NewAttribute(types.AttributeKeyCompletionTime, completionTime.Format(time.RFC3339)),
 		),
 		sdk.NewEvent(