Use canonical names for types in synthesized annotation toString

My proposal for the same change in the JDK is currently targeted for
JDK 19.

- https://bugs.openjdk.java.net/browse/JDK-8281462
- https://bugs.openjdk.java.net/browse/JDK-8281568
- https://github.com/openjdk/jdk/pull/7418

See gh-28015

spring-test/src/test/java/org/springframework/test/context/BootstrapUtilsTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2002-2020 the original author or authors.
+ * Copyright 2002-2022 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -72,8 +72,8 @@ class BootstrapUtilsTests {
 		assertThatIllegalStateException().isThrownBy(() ->
 				resolveTestContextBootstrapper(bootstrapContext))
 			.withMessageContaining("Configuration error: found multiple declarations of @BootstrapWith")
-			.withMessageContaining(FooBootstrapper.class.getName())
-			.withMessageContaining(BarBootstrapper.class.getName());
+			.withMessageContaining(FooBootstrapper.class.getCanonicalName())
+			.withMessageContaining(BarBootstrapper.class.getCanonicalName());
 	}
 
 	@Test