S3 repositories credentials should be filtered

When working on #18008 I found while reading the code that we don't filter anymore `repositories.s3.access_key` and `repositories.s3.secret_key`.

Also fixed a typo in REST test

plugins/repository-s3/src/main/java/org/elasticsearch/repositories/s3/S3Repository.java

@@ -67,13 +67,13 @@ public class S3Repository extends BlobStoreRepository {
          * @see CLOUD_S3#KEY_SETTING
          */
         Setting<String> KEY_SETTING =
-            new Setting<>("repositories.s3.access_key", CLOUD_S3.KEY_SETTING, Function.identity(), Property.NodeScope);
+            new Setting<>("repositories.s3.access_key", CLOUD_S3.KEY_SETTING, Function.identity(), Property.NodeScope, Property.Filtered);
         /**
          * repositories.s3.secret_key: AWS Secret key specific for all S3 Repositories API calls. Defaults to cloud.aws.s3.secret_key.
          * @see CLOUD_S3#SECRET_SETTING
          */
         Setting<String> SECRET_SETTING =
-            new Setting<>("repositories.s3.secret_key", CLOUD_S3.SECRET_SETTING, Function.identity(), Property.NodeScope);
+            new Setting<>("repositories.s3.secret_key", CLOUD_S3.SECRET_SETTING, Function.identity(), Property.NodeScope, Property.Filtered);
         /**
          * repositories.s3.region: Region specific for all S3 Repositories API calls. Defaults to cloud.aws.s3.region.
          * @see CLOUD_S3#REGION_SETTING

plugins/repository-s3/src/test/resources/rest-api-spec/test/repository_s3/20_repository.yaml

@@ -1,6 +1,6 @@
 # Integration tests for Repository S3 component
 #
-"S3 repository can be registereed":
+"S3 repository can be registered":
     - do:
         snapshot.create_repository:
           repository: test_repo_s3_1