Error when updating a dynamic association in a newly created object

[jsolari56]

This test also fails in master.

I created a PR for 6.0.x.BRINQA, but it might not be the best solution.

def "Test update newly created object"() {
    setup:
    def victor = new Pet(name: 'Victor')
    def fritz = new Pet(name: 'Fritz')
    def franz = new Pet(name: 'Franz')
    def heinrich = new Pet(name: 'Heinrich')
    victor.buddies = [fritz, franz]

    when:
    victor.save()
    heinrich.save()
    session.flush()

    then:
    victor.buddies.name.sort() == ['Franz', 'Fritz']

    when: "Adding an element"
    victor.buddies.add(heinrich)
    def cousin = victor.cousin

    then:
    victor.buddies.name.sort() == ['Franz', 'Fritz', 'Heinrich']

    when:
    victor.markDirty("buddies")
    victor.save()
    session.flush()
    victor.discard()
    victor = Pet.findByName("Victor")

    then:
    victor.buddies.name.sort() == ['Franz', 'Fritz', 'Heinrich']
}