Support @Sql and @SqlGroup on test interfaces

Status Quo

SPR-14184 introduced support for declaring test annotations on test interfaces for all class-level annotations in the Spring TestContext Framework except @Sql and @SqlGroup.

Analysis

As of Spring Framework 4.3, there is no first-class support in the framework for finding repeatable annotations like @Sql on interfaces with support for merged composed annotations without finding shadowed annotations on superclasses.

Deliverables

• Determine if it is feasible to implement a search algorithm for merged repeatable annotations on interfaces (i.e., something between the "get" and "find" variants in AnnotatedElementUtils).
• If it is feasible, support @Sql and @SqlGroup on test interfaces.