Search implemented interfaces on superclass for @ServiceConnection

Refine original fix to also search interfaces on the superclass.

Fixes gh-37671

spring-boot-project/spring-boot-testcontainers/src/main/java/org/springframework/boot/testcontainers/service/connection/ServiceConnectionContextCustomizerFactory.java

@@ -54,7 +54,10 @@ public ContextCustomizer createContextCustomizer(Class<?> testClass,
 	}
 
 	private void findSources(Class<?> clazz, List<ContainerConnectionSource<?>> sources) {
-		ReflectionUtils.doWithFields(clazz, (field) -> {
+		if (clazz == Object.class || clazz == null) {
+			return;
+		}
+		ReflectionUtils.doWithLocalFields(clazz, (field) -> {
 			MergedAnnotations annotations = MergedAnnotations.from(field);
 			annotations.stream(ServiceConnection.class)
 				.forEach((annotation) -> sources.add(createSource(field, annotation)));
@@ -65,6 +68,7 @@ private void findSources(Class<?> clazz, List<ContainerConnectionSource<?>> sour
 		for (Class<?> implementedInterface : clazz.getInterfaces()) {
 			findSources(implementedInterface, sources);
 		}
+		findSources(clazz.getSuperclass(), sources);
 	}
 
 	@SuppressWarnings("unchecked")

spring-boot-project/spring-boot-testcontainers/src/test/java/org/springframework/boot/testcontainers/service/connection/ServiceConnectionContextCustomizerFactoryTests.java

@@ -94,6 +94,14 @@ void createContextCustomizerWhenImplementedInterfaceHasServiceConnectionsReturns
 		assertThat(customizer.getSources()).hasSize(2);
 	}
 
+	@Test
+	void createContextCustomizerWhenInheritedImplementedInterfaceHasServiceConnectionsReturnsCustomizer() {
+		ServiceConnectionContextCustomizer customizer = (ServiceConnectionContextCustomizer) this.factory
+			.createContextCustomizer(ServiceConnectionsImplSubclass.class, null);
+		assertThat(customizer).isNotNull();
+		assertThat(customizer.getSources()).hasSize(2);
+	}
+
 	@Test
 	void createContextCustomizerWhenClassHasNonStaticServiceConnectionFailsWithHelpfulException() {
 		assertThatIllegalStateException()
@@ -186,6 +194,10 @@ static class ServiceConnectionsImpl implements ServiceConnectionsInterface {
 
 	}
 
+	static class ServiceConnectionsImplSubclass extends ServiceConnectionsImpl {
+
+	}
+
 	static class NonStaticServiceConnection {
 
 		@ServiceConnection