Update type check

- Check for a generic type before type name check.
- Replace `StartsWith()` with `==`.

Author: martincostello

src/OpenApi/src/Extensions/TypeExtensions.cs

@@ -19,7 +19,8 @@ public static bool IsJsonPatchDocument(this Type type)
         while (modelType != null && modelType != typeof(object))
         {
             if (modelType.Namespace == JsonPatchDocumentNamespace &&
-                (modelType.Name == JsonPatchDocumentName || modelType.Name.StartsWith(JsonPatchDocumentNameOfT, StringComparison.Ordinal)))
+                (modelType.Name == JsonPatchDocumentName ||
+                 (modelType.IsGenericType && modelType.GenericTypeArguments.Length == 1 && modelType.Name == JsonPatchDocumentNameOfT)))
             {
                 return true;
             }