release(required): api-graphql - default selection set regression

[iartemiev]

Description of changes

Issue #, if available

When generating the default selection set for a model, we were attempting to inject the groupsField of a static group auth rule e.g. a.allow.specificGroup('Admin'). Only dynamic group model introspection auth attributes contain a groupsField value, so we were inadvertently adding an explicit undefined to the default selection set, which was causing unexpected behavior.

This PR adds an additional check to make sure we're only adding the groupsField value when it's defined.

Description of how you validated changes

• Red/green TDD
• Manual e2e testing

Checklist

• PR description included
• yarn test passes
• Tests are changed or added
• Relevant documentation is changed or added (and PR referenced)

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[jimblanc]

Approving as a hot-fix, deferring to data team on the contents of the change