dialPhoneNumber method
Starts a phone all with the given phone number.
Requires permission CALL_PHONE
Implementation
Future<void> dialPhoneNumber(String phoneNumber) async {
assert(phoneNumber.isNotEmpty, "phoneNumber cannot be null or empty");
final Map<String, dynamic> args = {"phoneNumber": phoneNumber};
await _foregroundChannel.invokeMethod(DIAL_PHONE_NUMBER, args);
}