Field showing deprecated directive

Somehow field is showing deprecated
[screenshot](https://snag.gy/K7THjX.jpg)
code :
```
package main

import (
"fmt"
"net/http"

"github.com/graphql-go/graphql"
"github.com/graphql-go/handler"
)

var schema, _ = graphql.NewSchema(
graphql.SchemaConfig{
Query: graphql.NewObject(
graphql.ObjectConfig{
Name: "Query",
Fields: graphql.Fields{
"healthz": &graphql.Field{
Type: graphql.String,
Resolve: func(p graphql.ResolveParams) (interface{}, error) {
return "ok", nil
},
},
},
},
),
Mutation: graphql.NewObject(
graphql.ObjectConfig{
Name: "Mutation",
Fields: graphql.Fields{
"healthz": &graphql.Field{
Type: graphql.String,
Resolve: func(p graphql.ResolveParams) (interface{}, error) {
return "ok", nil
},
},
},
},
),
},
)

var port = ":8080"

func main() {

http.Handle("/", handler.New(&handler.Config{
Schema: &schema,
GraphiQL: false,
Playground: true,
}))
fmt.Println("Now server is running on port " + port)
http.ListenAndServe(port, nil)
}
```

how to remove deprecated directive ?