still trying to fix primary resource decoding error

Author: mattpolzin

Sources/JSONAPI/Document/DocumentDecodingError.swift

@@ -33,10 +33,10 @@ public enum DocumentDecodingError: Swift.Error, Equatable {
             self = .primaryResourceMissing
         case .valueNotFound(let type, let context) where Location(context) == .data && type == UnkeyedDecodingContainer.self:
             self = .primaryResourcesMissing
-        case .typeMismatch(let type, let context) where Location(context) == .data && type is AbstractResourceObject.Type && context.debugDescription.hasSuffix("but found null instead."):
-            self = .primaryResourceMissing
         case .typeMismatch(let type, let context) where Location(context) == .data && type == UnkeyedDecodingContainer.self && context.debugDescription.hasSuffix("but found null instead."):
             self = .primaryResourcesMissing
+        case .typeMismatch(_, let context) where Location(context) == .data && context.debugDescription.hasSuffix("but found null instead."):
+            self = .primaryResourceMissing
         default:
             return nil
         }