readme needs updating

[MichaelOsowski]

Description

[TIP]: # ( query GetDashboardPages {
actor {
entity(guid: "DASHBOARD_GUID") {
... on DashboardEntity {
pages {
guid
name
}
}
}
}
}
)

need to use mutation above to the the correct guid

[sdewitt-newrelic]

Hi @MichaelOsowski can you include the GraphQL mutation you had to use instead?