message: fix(typegoose::getModelWithString): allow specifying QueryHelpers for return model
diff: @@ -110,7 +110,9 @@ export function getModelForClass<U extends AnyParamConstructor<any>, QueryHelper
  * const NameModel = getModelWithString<typeof ClassName>("ClassName");
  * ```
  */
  -export function getModelWithString<U extends AnyParamConstructor<any>>(key: string): undefined | ReturnModelType<U> {
  +export function getModelWithString<U extends AnyParamConstructor<any>, QueryHelpers = BeAnObject>(
  + key: string
  +): undefined | ReturnModelType<U, QueryHelpers> {
  assertion(typeof key === 'string', () => new ExpectedTypeError('key', 'string', key));
  return models.get(key) as any;
  