added delete server code

[cfoskin]

Motivation

The UI will need server code to delete a resolver

What

The server code to remove one resolver

Why

How

create the mutation code and resolver

Verification Steps

Create a schema

type Note {
	id: Int!
	ownerId: Int!
	content: String
}

type Query {
	listNotes: [Note]
}

Create a resolver

mutation upsertResolver {
  upsertResolver(schemaId: 1, dataSourceId: 1, type: "Note", field: "text", requestMapping: "test", responseMapping: "gjg") {
    id
  }
}

Test the new resolver using the following query from graphiql

mutation deleteResolver{
 	deleteResolver(id: 1) {
    id
    type
    requestMapping
    responseMapping
  } 
}

Checklist:

• Code has been tested locally by PR requester
• Changes have been successfully verified by another team member

Progress

• Finished task
• TODO

Additional Notes

[pb82]

👀

[pb82]

LGTM, verified locally