Support GraphQL mutation as list

[raminqaf]

Currently, we are only supporting mutation over a single object. For example:

input ProductInput {
    name: String
    color: String
}

type Product {
    id: ID
    name: String
    color: String
}

type Mutation {
    setProduct(id: ID, product: ProductInput): Product @topic(name: "product-topic")
}

and we can do the mutation like this:

mutation {
	setProduct(id:"abc", product: {name: "test-1", color: "red"}) {
		id
	}
}

However, we need to support mutations with lists so we can ingest a list of objects over a single call:

input ProductInput {
    name: String
    color: String
}

type Product {
    id: ID
    name: String
    color: String
}

type Mutation {
    setProduct(ids: [ID], products: [ProductInput]): [Product] @topic(name: "product-topic")
}

and we can do the mutation like this:

mutation {
	setProduct(ids:["abc", "efg"], product: [{name: "test-1", color: "red"}, {name: "test-2", color: "blue"}]) {
		id
	}
}