goctl rpc client generate go file not reuse connection lead to goroutine leak

[zou-xinhua]

Describe the bug
A clear and concise description of what the bug is.

To Reproduce
Steps to reproduce the behavior, if applicable:

1. The code is

   {{.head}}

package {{.filePackage}}

import (
"context"

{{.pbPackage}}
{{if ne .pbPackage .protoGoPackage}}{{.protoGoPackage}}{{end}}

"github.com/zeromicro/go-zero/zrpc"
"google.golang.org/grpc"

)

type (
{{.alias}}

{{.serviceName}} interface {
	{{.interface}}
}

default{{.serviceName}} struct {
	cli zrpc.Client
}

)

func New{{.serviceName}}(cli zrpc.Client) {{.serviceName}} {
return &default{{.serviceName}}{
cli: cli,
}
}

{{if .hasComment}}{{.comment}}{{end}}
func (m *default{{.serviceName}}) {{.method}}(ctx context.Context{{if .hasReq}}, in {{.pbRequest}}{{end}}, opts ...grpc.CallOption) ({{if .notStream}}{{.pbResponse}}, {{else}}{{.streamBody}},{{end}} error) {
client := {{.package}}.New{{.rpcServiceName}}Client(m.cli.Conn())
return client.{{.method}}(ctx{{if .hasReq}}, in{{end}}, opts...)
}

2. The error is

**Expected behavior**
A clear and concise description of what you expected to happen.
、、、
type defaultManager struct {
 cli    zrpc.Client
 client ManagerClient // 复用 gRPC 客户端
}

func NewManager(cli zrpc.Client) Manager {
 return &defaultManager{
     cli:    cli,
     client: NewManagerClient(cli.Conn()), // 初始化时创建客户端
 }
}

func (m *defaultManager) SetBaseHostResource(ctx context.Context, in *SetBaseHostResourceRequest, opts ...grpc.CallOption) (*SetBaseHostResourceResponse, error) {
 return m.client.SetBaseHostResource(ctx, in, opts...) // 直接使用复用的客户端
}
、、、
**Screenshots**
If applicable, add screenshots to help explain your problem.

**Environments (please complete the following information):**
- OS: [e.g. Linux]
- go-zero version [v1.3.2]
- goctl version [goctl version 1.3.2 darwin/amd64]

**More description**
Add any other context about the problem here.

![Image](https://github.com/user-attachments/assets/c35d39b1-0359-4f5e-9962-872bb1321e65)