Fix multi-release JAR issue with VirtualThreadDelegate

[bclozel]

As seen in #35767, VirtualThreadDelegate has an invalid entry:

jar --validate --file /Users/cwalker/public-repos/spring-framework/spring-core/build/libs/spring-core-7.0.0-SNAPSHOT.jar
entry: META-INF/versions/21/org/springframework/core/task/VirtualThreadDelegate.class, contains a class with different api from earlier version

[github-actions]

Fixed via f0cf7f1