logout method
Implementation
Future<void> logout() async {
if (Platform.isIOS) {
final browser = ChromeSafariBrowser();
await browser.open(url: _buildEndSessionUrl()).then((value) async {
await browser.close();
});
} else {
await launch(_buildEndSessionUrl().toString());
}
_kindeApi.setBearerAuth(_bearerAuth, '');
await Store.instance.clear();
}