V1.0.0 onRender fails if a sheet inheriting from GurpsActorGcsSheet has no quick notes

[StefanLeng]

I have no quick note section in my sheet that inherits from GurpsActorGcsSheet , The line elements.push(this.element.querySelector('.quick-notes')!)
in _onRender pushes null into the array, that causes the subsequent operations to fail with an null dererfernce error.