`JdbcRepositoryConfigExtension` does not report repository base class name

[mp911de]

The class name is required to correctly determine AOT repository metadata and so fragments in the metadata appear with org.springframework.data.repository.config.RepositoryBeanDefinitionReader$Dummy.

    {
      "name": "saveAll",
      "signature": "org.springframework.data.repository.config.RepositoryBeanDefinitionReader$Dummy",
      "fragment": {
        "interface": "org.springframework.data.repository.config.RepositoryBeanDefinitionReader$Dummy",
        "fragment": "org.springframework.data.repository.config.RepositoryBeanDefinitionReader$Dummy"
      }
    }