Add image_node and vfolder_node fields to ComputeSessionNode type schema

[fregataa]

Motivation  

• The data schema of Compute sessions has images and vfolder mounts fields but GQL schema doesn’t
• The data schema of Compute kernels has an image and architecture fields but GQL schema doesn’t

Schema updates

type KernelNode implements Node {
  # New fields
  image_reference: String
  architecture: String
}

type ComputeSessionNode implements Node {
  # New fields
  image_references: [String]
  vfolder_nodes(filter: String, order: String, offset: Int, before: String, after: String, first: Int, last: Int): VirtualFolderConnection
}

Testing Scenarios  

Query ComputeSessionNode & KernelNode

query Session {
    compute_session_nodes(
        scope_id: "project:2de2b969-1d04-48a6-af16-0bc8adb3c831",
    ) {
        edges {
            cursor
            node {
                id
                name
                image_references
                vfolder_nodes {
                    edges {
                        node {
                            id
                            row_id
                            name
                            permissions
                        }
                    }
                }
                kernel_nodes {
                    edges {
                        node {
                            id
                            row_id
                            image {
                                id
                                row_id
                                name
                            }
                        }
                    }
                }
            }
        }
    }
}