Remove duplicated image name in image JSON output (#1655)

https://github.com/apple/container/pull/1652 rearranged the JSON output
for image resources and included a duplicate "name" field. After further
discussion, we've decided to remove the duplicate field.

Signed-off-by: Kathryn Baldauf <k_baldauf@apple.com>

Sources/ContainerResource/Image/ImageResource.swift

@@ -112,7 +112,6 @@ extension ImageResource {
 extension ImageResource {
     enum CodingKeys: String, CodingKey {
         case id
-        case name
         case configuration
         case variants
     }
@@ -120,7 +119,6 @@ extension ImageResource {
     public func encode(to encoder: Encoder) throws {
         var container = encoder.container(keyedBy: CodingKeys.self)
         try container.encode(id, forKey: .id)
-        try container.encode(name, forKey: .name)
         try container.encode(configuration, forKey: .configuration)
         try container.encode(variants, forKey: .variants)
     }