OZG-3936 OZG-7793 Autowire instead of constructor injection

alfa-service/src/main/java/de/ozgcloud/alfa/common/LinkedUserProfileResourceSerializer.java

@@ -28,6 +28,7 @@ import java.lang.reflect.InvocationTargetException;
 import java.util.Collection;
 
 import org.apache.commons.lang3.reflect.ConstructorUtils;
+import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.hateoas.Link;
 import org.springframework.stereotype.Component;
 
@@ -44,16 +45,18 @@ import de.ozgcloud.common.errorhandling.TechnicalException;
 @Component
 public class LinkedUserProfileResourceSerializer extends JsonSerializer<Object> implements ContextualSerializer {
 
+	// need to autowire, because Spring calls the constructor without parameters
+	@Autowired
 	private final UserManagerUrlProvider userManagerUrlProvider;
 
 	private LinkedUserProfileResource annotation;
 
 	// for usage outside of Spring
 	private LinkedUserProfileResourceSerializer() {
-		this.userManagerUrlProvider = new UserManagerUrlProvider(new UserManagerProperties());
+		this(new UserManagerUrlProvider(new UserManagerProperties()));
 	}
 
-	public LinkedUserProfileResourceSerializer(UserManagerUrlProvider userManagerUrlProvider) {
+	private LinkedUserProfileResourceSerializer(UserManagerUrlProvider userManagerUrlProvider) {
 		this.userManagerUrlProvider = userManagerUrlProvider;
 	}