Add Contacts to User

[derek-etherton-opslevel]

Problem

The User struct does not have Contacts.

Solution

Add Contacts to the User struct.

Unit tests should be good, but manually verified w/ this:

func main() {
	apiToken := os.Getenv("OPSLEVEL_API_TOKEN")
	if apiToken == "" {
		log.Fatal("OPSLEVEL_API_TOKEN environment variable is not set")
	}

	client := opslevel.NewGQLClient(opslevel.SetAPIToken(apiToken))

	users, err := client.ListUsers(nil)
	if err != nil {
		log.Fatalf("Failed to list users: %v", err)
	}

	for _, user := range users.Nodes {
		fmt.Printf("User: %s\n", user.Name)
		fmt.Printf("Contacts: %+v\n", user.Contacts)
	}
}

Checklist

• I have run this code, and it appears to resolve the stated issue.
• This PR does not reduce total test coverage
• This PR has no user interface changes or has already received approval from product management to change the interface.
• Does this change require a Terraform schema change?
  • If so what is the ticket or PR #
• Make a changie entry that explains the customer facing outcome of this change

[jasonopslevel]

lgtm