Remove `@RunWith(SpringRunner.class)` from sample code in Spring Integration Test Binder section:
1. It is a JUnit4 annotation
2. `@SpringBootTest` composes the JUnit5 counterpart (`@ExtendWith({SpringExtension.class})`)
Resolves #2537
Remove `@RunWith(SpringRunner.class)` from sample code in Spring Integration Test Binder section:
1. It is a JUnit4 annotation
2. `@SpringBootTest` composes the JUnit5 counterpart (`@ExtendWith({SpringExtension.class})`)
Resolves #2537