Deprecation notices on PHP 8.1

[benr77]

Under PHP 8.1 I get the following deprecation notices:

PHP Deprecated:  Return type of DZunke\FeatureFlagsBundle\Toggle\ConditionBag::getIterator() should 
either be compatible with IteratorAggregate::getIterator(): Traversable, or the #[\ReturnTypeWillChange] 
attribute should be used to temporarily suppress the notice in /var/www/app/vendor/dzunke/feature-flags-
bundle/DZunke/FeatureFlagsBundle/Toggle/ConditionBag.php on line 18

PHP Deprecated:  Return type of DZunke\FeatureFlagsBundle\Toggle\ConditionBag::count() should either 
be compatible with Countable::count(): int, or the #[\ReturnTypeWillChange] attribute should be used to
 temporarily suppress the notice in /var/www/app/vendor/dzunke/feature-flags-
bundle/DZunke/FeatureFlagsBundle/Toggle/ConditionBag.php on line 26