[bs-143] Add LiveBeansView to Actuator app on /beans

As per standard LiveBeansView features, if spring.liveBeansView.mbeanDomain
is set in the Environment, then all application contexts are displayed,
otherwise only the local one.  Only JSON is served (via produces=).

[Fixes #50879457]

spring-bootstrap-samples/spring-bootstrap-actuator-sample/src/test/java/org/springframework/bootstrap/sample/test/ServiceBootstrapApplicationTests.java

@@ -128,6 +128,19 @@ public class ServiceBootstrapApplicationTests {
 		assertEquals(999, body.get("status"));
 	}
 
+	@Test
+	public void testBeans() throws Exception {
+		@SuppressWarnings("rawtypes")
+		ResponseEntity<List> entity = getRestTemplate("user", "password").getForEntity(
+				"http://localhost:8080/beans", List.class);
+		assertEquals(HttpStatus.OK, entity.getStatusCode());
+		assertEquals(1, entity.getBody().size());
+		@SuppressWarnings("unchecked")
+		Map<String, Object> body = (Map<String, Object>) entity.getBody().get(0);
+		assertTrue("Wrong body: " + body,
+				((String) body.get("context")).startsWith("org.springframework"));
+	}
+
 	private RestTemplate getRestTemplate() {
 		return getRestTemplate(null, null);
 	}