Invalidate the 'rendered' cache tag whenever the settings are modified.
\Drupal\Core\Config\ConfigCrudEvent $event: The Event to process.
public function onSave(ConfigCrudEvent $event) {
if ($event
->getConfig()
->getName() === 'paragraphs_collection.settings') {
// Invalidate caches.
$this->cacheTagsInvalidator
->invalidateTags([
'rendered',
]);
}
}