Testing MatOptionHarness in MatSelectHarness

Reminder to self: When trying to get the options in the MatSelectHarness in Angular Material, you need to simulate a click on the MatSelectHarness - await select.open();, else the MatOptions will not be loaded.

it('should display the options for the select', async () => {
    let field = await loader.getHarness(MatFormFieldHarness.with({floatingLabelText: 'Country *'}))
    let select = await field.getControl() as MatSelectHarness;
    expect(select).toBeTruthy();
    await select.open();
    let options = await select.getOptions();
    expect(options.length).toBe(countries.length);
});