Upgrade cobra and use new feature

Upgraded cobra by "go get -u github.com/spf13/cobra && go mod tidy"

cmd/reduceclustercapacity.go

@@ -39,6 +39,8 @@ that belong to the auto scaling group or spot fleet request.`,
 
 	cmd.Flags().String("auto-scaling-group-name", "", "The name of the target `GROUP`")
 	cmd.Flags().String("spot-fleet-request-id", "", "The ID of the target `REQUEST`")
+	cmd.MarkFlagsOneRequired("auto-scaling-group-name", "spot-fleet-request-id")
+	cmd.MarkFlagsMutuallyExclusive("auto-scaling-group-name", "spot-fleet-request-id")
 
 	cmd.Flags().String("cluster", "default", "The name of the target `CLUSTER`")
 
@@ -54,9 +56,6 @@ func reduceClusterCapacity(cmd *cobra.Command, args []string) error {
 	cluster, _ := reduceClusterCapacityCmd.Flags().GetString("cluster")
 	amount, _ := reduceClusterCapacityCmd.Flags().GetInt32("amount")
 
-	if len(id) == 0 && len(name) == 0 {
-		return errors.New("\"spot-fleet-request-id\" or \"auto-scaling-group-name\" is required")
-	}
 	if amount <= 0 {
 		return errors.New("\"amount\" must be greater than 0")
 	}

go.mod

@@ -11,7 +11,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/ecs v1.48.0
 	github.com/aws/aws-sdk-go-v2/service/eventbridge v1.35.2
 	github.com/aws/aws-sdk-go-v2/service/sqs v1.36.2
-	github.com/spf13/cobra v1.1.1
+	github.com/spf13/cobra v1.8.1
 	go.uber.org/mock v0.5.0
 	golang.org/x/xerrors v0.0.0-20200804184101-5ec99f83aff1
 )
@@ -29,7 +29,7 @@ require (
 	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.28.2 // indirect
 	github.com/aws/aws-sdk-go-v2/service/sts v1.32.2 // indirect
 	github.com/aws/smithy-go v1.22.0 // indirect
-	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
 	github.com/jmespath/go-jmespath v0.4.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 )