Reset replication state when active cluster changed (#8233)

## What changed?
Reset replication state when active cluster changed

## Why?
When the active cluster changes, we treat it a failover happens,
graceful or forceful. It should clean the state.

## How did you test it?
- [ ] built
- [ ] run locally and tested manually
- [ ] covered by existing tests
- [ ] added new unit test(s)
- [ ] added new functional test(s)

Author: yux0

service/frontend/namespace_handler.go

@@ -513,6 +513,7 @@ func (d *namespaceHandler) UpdateNamespace(
 		if updateReplicationConfig.GetActiveClusterName() != "" {
 			activeClusterChanged = true
 			replicationConfig.ActiveClusterName = updateReplicationConfig.GetActiveClusterName()
+			replicationConfig.State = enumspb.REPLICATION_STATE_NORMAL
 		}
 	}
 
@@ -884,7 +885,7 @@ func (d *namespaceHandler) createResponse(
 	replicationConfigResult := &replicationpb.NamespaceReplicationConfig{
 		ActiveClusterName: replicationConfig.ActiveClusterName,
 		Clusters:          clusters,
-		State:             replicationConfig.State,
+		State:             replicationConfig.GetState(),
 	}
 
 	var failoverHistory []*replicationpb.FailoverStatus

service/frontend/namespace_handler_test.go

@@ -679,7 +679,7 @@ func (s *namespaceHandlerCommonSuite) TestUpdateNamespace_UpdateActiveClusterWit
 			ReplicationConfig: &persistencespb.NamespaceReplicationConfig{
 				ActiveClusterName: clusterName2,
 				Clusters:          []string{clusterName1, clusterName2},
-				State:             enumspb.REPLICATION_STATE_HANDOVER,
+				State:             enumspb.REPLICATION_STATE_NORMAL,
 				FailoverHistory: []*persistencespb.FailoverStatus{
 					{
 						FailoverTime:    timestamppb.New(update1Time),
@@ -754,6 +754,7 @@ func (s *namespaceHandlerCommonSuite) TestUpdateNamespace_ChangeActiveClusterWit
 			ReplicationConfig: &persistencespb.NamespaceReplicationConfig{
 				ActiveClusterName: clusterName2,
 				Clusters:          []string{clusterName1, clusterName2},
+				State:             enumspb.REPLICATION_STATE_NORMAL,
 				FailoverHistory: []*persistencespb.FailoverStatus{
 					{
 						FailoverTime:    timestamppb.New(update1Time),
@@ -865,6 +866,7 @@ func (s *namespaceHandlerCommonSuite) TestUpdateNamespace_UpdateActiveCluster_Li
 			ReplicationConfig: &persistencespb.NamespaceReplicationConfig{
 				ActiveClusterName: clusterName2,
 				Clusters:          []string{clusterName1, clusterName2},
+				State:             enumspb.REPLICATION_STATE_NORMAL,
 				FailoverHistory:   sizeLimitedFailoverHistory,
 			},
 			ConfigVersion:               0,
@@ -1147,6 +1149,7 @@ func (s *namespaceHandlerCommonSuite) TestUpdateLocalNamespace_AllAttrSet() {
 			ReplicationConfig: &persistencespb.NamespaceReplicationConfig{
 				ActiveClusterName: activeClusterName,
 				Clusters:          []string{activeClusterName},
+				State:             enumspb.REPLICATION_STATE_NORMAL,
 			},
 			ConfigVersion:               1,
 			FailoverNotificationVersion: 0,
@@ -1666,6 +1669,7 @@ func (s *namespaceHandlerCommonSuite) TestFailoverGlobalNamespace_NotMaster() {
 			ReplicationConfig: &persistencespb.NamespaceReplicationConfig{
 				ActiveClusterName: clusterName2,
 				Clusters:          []string{clusterName1, clusterName2},
+				State:             enumspb.REPLICATION_STATE_NORMAL,
 				FailoverHistory: []*persistencespb.FailoverStatus{
 					{
 						FailoverTime:    timestamppb.New(update1Time),