Update CHANGELOG for #5859

CHANGELOG.md

@@ -12,6 +12,7 @@ ENHANCEMENTS:
 * resource/aws_db_instance: Add `domain` and `domain_iam_role_name` arguments (support for domain joining RDS instances) [GH-5378]
 * resource/aws_ecs_task_definition: Suppress `container_definition` differences for equivalent port and host mappings [GH-5833]
 * resource/aws_ecs_task_definition: Add docker volume configuration [GH-5727]
+* resource/aws_iam_role: Allow empty string (`""`) value for `permissions_boundary` argument [GH-5859]
 * resource/aws_iot_topic_rule: Add `firehose` `seperator` argument [GH-5734]
 * resource/aws_launch_template: Allow `network_interface` `ipv4_address_count` configuration [GH-5830]
 * resource/aws_ssm_document: Add support for `Session` `document_type` [GH-5850]