Enable configuration properties scanning in smoke tests that need it

Closes gh-18674

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-actuator-noweb/src/main/java/smoketest/actuator/noweb/SampleActuatorNoWebApplication.java

@@ -18,8 +18,10 @@ package smoketest.actuator.noweb;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.ConfigurationPropertiesScan;
 
 @SpringBootApplication
+@ConfigurationPropertiesScan
 public class SampleActuatorNoWebApplication {
 
 	public static void main(String[] args) {

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-actuator/src/main/java/smoketest/actuator/SampleActuatorApplication.java

@@ -20,9 +20,11 @@ import org.springframework.boot.SpringApplication;
 import org.springframework.boot.actuate.health.Health;
 import org.springframework.boot.actuate.health.HealthIndicator;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.ConfigurationPropertiesScan;
 import org.springframework.context.annotation.Bean;
 
 @SpringBootApplication
+@ConfigurationPropertiesScan
 public class SampleActuatorApplication {
 
 	public static void main(String[] args) {

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-property-validation/src/main/java/smoketest/propertyvalidation/SamplePropertyValidationApplication.java

@@ -19,10 +19,12 @@ package smoketest.propertyvalidation;
 import org.springframework.boot.CommandLineRunner;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
 import org.springframework.boot.builder.SpringApplicationBuilder;
+import org.springframework.boot.context.properties.ConfigurationPropertiesScan;
 import org.springframework.context.annotation.Bean;
 import org.springframework.validation.Validator;
 
 @SpringBootApplication
+@ConfigurationPropertiesScan
 public class SamplePropertyValidationApplication implements CommandLineRunner {
 
 	private final SampleProperties properties;

spring-boot-tests/spring-boot-smoke-tests/spring-boot-smoke-test-test/src/main/java/smoketest/test/SampleTestApplication.java

@@ -18,6 +18,7 @@ package smoketest.test;
 
 import org.springframework.boot.SpringApplication;
 import org.springframework.boot.autoconfigure.SpringBootApplication;
+import org.springframework.boot.context.properties.ConfigurationPropertiesScan;
 
 /**
  * Sample application to demonstrate testing.
@@ -25,6 +26,7 @@ import org.springframework.boot.autoconfigure.SpringBootApplication;
  * @author Phillip Webb
  */
 @SpringBootApplication
+@ConfigurationPropertiesScan
 public class SampleTestApplication {
 
 	// NOTE: this application will intentionally not start without MySQL, the test will