Fix incomplete assertions

Closes gh-7907

spring-boot-actuator/src/test/java/org/springframework/boot/actuate/health/MongoHealthIndicatorTests.java

@@ -85,8 +85,8 @@ public class MongoHealthIndicatorTests {
 		MongoHealthIndicator healthIndicator = new MongoHealthIndicator(mongoTemplate);
 		Health health = healthIndicator.health();
 		assertThat(health.getStatus()).isEqualTo(Status.DOWN);
-		assertThat(((String) health.getDetails().get("error"))
-				.contains("Connection failed"));
+		assertThat((String) health.getDetails().get("error"))
+				.contains("Connection failed");
 		verify(mongoTemplate).executeCommand("{ buildInfo: 1 }");
 	}
 

spring-boot/src/test/java/org/springframework/boot/SpringApplicationTests.java

@@ -816,7 +816,7 @@ public class SpringApplicationTests {
 		this.context = application.run();
 		assertThat(this.context.getEnvironment())
 				.isNotInstanceOf(StandardServletEnvironment.class);
-		assertThat(this.context.getEnvironment().getProperty("foo"));
+		assertThat(this.context.getEnvironment().getProperty("foo")).isEqualTo("bar");
 		assertThat(this.context.getEnvironment().getPropertySources().iterator().next()
 				.getName()).isEqualTo(
 						TestPropertySourceUtils.INLINED_PROPERTIES_PROPERTY_SOURCE_NAME);