Add awaiting wrapped object section to Retry-ability guide

[amirrustam]

The Retry-ability guide demonstrates assertions on DOM elements, but the concept of retrying assertions also applies to regular objects via cy.wrap. Example:

  it('waits for changed property value', () => {
    const o = { foo: 20 }

    // changes property "foo" after delay
    setTimeout(() => {
      o.foo = 42
    }, 100)

    // "expect" syntax does NOT work
    // because it is not retried!
    // expect(o).to.have.property('foo', 42)

    // wrapping an object and using "should" syntax retries
    // the assertion until the "o.foo = 42" runs and the assertion passes
    cy.wrap(o).should('have.property', 'foo', 42)
  })

🔗 Source and more examples

This ability should also be stated in this guide. We already seen a large user create work-arounds because they did not know about using cy.wrap to wait on object changes.

[bahmutov]

also this blog post that talks about Redux store might point it out explicitly https://github.com/cypress-io/cypress-example-recipes#blogs "Testing Redux Store"

AND it needs link to the actual blog post https://www.cypress.io/blog/2018/11/14/testing-redux-store/ !! And we need to call attention to automatic retrying of cy.window().its('STORE_NAME').should('exist')