a suggestion for minSize operator enhancement

[ByungjunYou]

Describe the feature you request

When setting a collection with fixture monkey operator minSize, then I expect it to be NOT null.

For example, it would be nice to have tearchers which is always NOT null in the below circumstance. The rational behind this is that if the size of a collection is greater than 0, the collection should not be null.

fun school(fixture: FixtureMonkey): ArbitraryBuilder<School> = 
  fixture.giveMeBuilder(School::class.java)
    .minSize("teachers", 1)

data class School() {
  val teachers: List<Teacher>
}

If the feature request is approved, would you be willing to submit a PR?

Yes