fix(DatePicker): protect flatpickr in shallow render tests (#1389)
fix(DatePicker): protect flatpickr in shallow render tests (#1389)

* fix(DatePicker): protect flatpickr in shallow render tests

* fix(DatePicker): add comment to describe the Null check

carbon-design-system/carbon-components-react,carbon-design-system/carbon-components,joshblack/carbon-components-react,joshblack/carbon-components-react,carbon-design-system/carbon-components,carbon-design-system/carbon-components-react,carbon-design-system/carbon-components