Protect against stack overflow when searching meta annotations

It is legal for an annotation to be annotated with itself. Previously,
when searching for meta annotations this could lead to a stack overflow.
This was likely to occur when using Kotlin as, like Java, its Target
annotation is annotated with itself. A stack overflow doesn’t occur
with Java’s Target annotation due to some short-circuiting logic for
annotations in java.lang.

This commit updates the logic for finding meta-annotations to
short-circuit when an annotation that has already been seen is
encountered.

Closes gh-5902

spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/properties/AnnotationsPropertySourceTests.java

@@ -164,6 +164,11 @@ public class AnnotationsPropertySourceTests {
 		assertThat(source.getProperty("aliasing.value")).isEqualTo("baz");
 	}
 
+	@Test
+	public void selfAnnotatingAnnotationDoesNotCauseStackOverflow() {
+		new AnnotationsPropertySource(PropertyMappedWithSelfAnnotatingAnnotation.class);
+	}
+
 	static class NoAnnotation {
 
 	}
@@ -327,7 +332,9 @@ public class AnnotationsPropertySourceTests {
 	static @interface AttributeWithAliasAnnotation {
 
 		@AliasFor(annotation = AliasedAttributeAnnotation.class, attribute = "value")
-		String value() default "foo";
+		String value()
+
+		default "foo";
 
 		String someOtherAttribute() default "shouldNotBeMapped";
 
@@ -341,4 +348,15 @@ public class AnnotationsPropertySourceTests {
 
 	}
 
+	@Retention(RetentionPolicy.RUNTIME)
+	@SelfAnnotating
+	static @interface SelfAnnotating {
+
+	}
+
+	@SelfAnnotating
+	static class PropertyMappedWithSelfAnnotatingAnnotation {
+
+	}
+
 }