defaultInputDecoration function
returns default InputDecoration for AppTextField widget
Implementation
InputDecoration defaultInputDecoration(
    {String? hint, String? label, TextStyle? textStyle}) {
  return InputDecoration(
    labelText: label,
    hintText: hint,
    hintStyle: textStyle,
    labelStyle: textStyle,
    border: OutlineInputBorder(),
    alignLabelWithHint: true,
  );
}