Consider to introduce @StreamTest for SCSt-specific slices to test

See Spring Boot Reference Manual for more info.

This one might be marked with something like:

public @interface AutoConfigureTestBinder {

	/**
	 * If {@link TestSupportBinderAutoConfiguration} should be appied.
         * Defaults to {@code true}
	 * @return if test binder support is enabled
	 */
	boolean enabled() default true;

}

Right now we can exclude that one only via:

@SpringBootTest(
		properties = "spring.autoconfigure.exclude=org.springframework.cloud.stream.test.binder.TestSupportBinderAutoConfiguration")

which is not so convenient and obvious.

Start with the Spring Boot testing reference and the current SpringBootTest exclusion for TestSupportBinderAutoConfiguration. Define the proposed @StreamTest and AutoConfigureTestBinder behavior, including the enabled default, and verify that SCSt-specific slice tests can control the test binder without the properties workaround.