Add nullability annotations to tests in module/spring-boot-data-jdbc

See gh-47263

module/spring-boot-data-jdbc/build.gradle

@@ -39,3 +39,7 @@ dependencies {
 	testRuntimeOnly("com.h2database:h2")
 	testRuntimeOnly("com.zaxxer:HikariCP")
 }
+
+tasks.named("compileTestJava") {
+	options.nullability.checking = "tests"
+}

module/spring-boot-data-jdbc/src/test/java/org/springframework/boot/data/jdbc/autoconfigure/DataJdbcRepositoriesAutoConfigurationTests.java

@@ -126,6 +126,7 @@ class DataJdbcRepositoriesAutoConfigurationTests {
 			.run((context) -> {
 				JdbcMappingContext mappingContext = context.getBean(JdbcMappingContext.class);
 				ManagedTypes managedTypes = (ManagedTypes) ReflectionTestUtils.getField(mappingContext, "managedTypes");
+				assertThat(managedTypes).isNotNull();
 				assertThat(managedTypes.toList()).containsOnly(City.class);
 			});
 	}