Helpers function for all events related to focus/blur of CVV field for card flipping effects. See examples in the demo folder of the git repo for some example on how to use this module.
onFocus event for the CVV field.
This will update the focus state of the cvv field to True in the internal state
onBlur event for the CVV field.
This will update the focus state of the cvv field to False in the internal state
Helper function to update the focus state of the cvv field in the internal state