fixed static failed test

Author: Usik2203

lib/internal/Magento/Framework/Setup/Declaration/Schema/Db/StatementAggregator.php

@@ -10,6 +10,8 @@
  * Statement aggregator.
  *
  * Statements are concatenated conditionally, decides which statements go separately and which may be concatenated.
+ *
+ * @api
  */
 class StatementAggregator
 {

lib/internal/Magento/Framework/Setup/Declaration/Schema/Dto/Schema.php

@@ -11,6 +11,8 @@
  * Schema DTO element.
  *
  * Aggregation root for all structural elements. Provides access to tables by their names.
+ *
+ * @api
  */
 class Schema
 {

lib/internal/Magento/Framework/Setup/Declaration/Schema/ElementHistory.php

@@ -12,6 +12,8 @@
  * Element history container.
  *
  * This class holds history about element modifications.
+ *
+ * @api
  */
 class ElementHistory
 {