Issue #3208268: Make the implications of caching clearer

src/Plugin/KeyProvider/AwsSecretsManagerKeyProvider.php

@@ -189,7 +189,7 @@ class AwsSecretsManagerKeyProvider extends KeyProviderBase implements KeyProvide
     $form['cache_max_age'] = [
       '#type' => 'select',
       '#title' => $this->t('Cache maximum age'),
-      '#description' => $this->t('The maximum time the secret should be cached locally after fetching from AWS Secrets Manager.'),
+      '#description' => $this->t('The maximum time the secret should be cached locally after fetching from AWS Secrets Manager.<br/><strong>Important:</strong> Caching may store the value in the database and your backups, depending on configuration.'),
       '#options' => $period,
       '#default_value' => $this->getConfiguration()['cache_max_age'] ?? self::CACHE_DISABLED,
     ];