Remove empty test

The caching behaviour when using ImportAutoConfiguration is covered
by tests in spring-boot-test-auto-configuration, specifically by
ImportsContextCustomizerFactoryWithAutoConfigurationTests.

See gh-7953

spring-boot-test/src/test/java/org/springframework/boot/test/context/ImportsContextCustomizerTests.java

@@ -55,11 +55,6 @@ public class ImportsContextCustomizerTests {
 								SecondDeterminableImportSelectorAnnotatedClass.class));
 	}
 
-	@Test
-	public void importAutoConfigurationCanIgnoreAdditionalAnnotations() throws Exception {
-
-	}
-
 	@Test
 	public void customizersForTestClassesWithDifferentKotlinMetadataAreEqual() {
 		assertThat(new ImportsContextCustomizer(FirstKotlinAnnotatedTestClass.class))