Compilation issue in Groovy 4

We migrate the application to Groovy 4 and got an issue:

1) We use GroovyClassLoader to load *.groovy written classes to a classloader

2) Before the migration we used Groovy 3.0.15.

3) After the migration to 4.0.10 I've got the following error:

Only classes and closures can be used for attribute 'value' in @org.openl.rules.ruleservice.core.annotations.ServiceExtraMethod
 @ line 18, column 30.
       @ServiceExtraMethod(value = org.openl.generated.services.ServiceExtraMethodHandler2Impl.class)
                                ^ 

4) If the annotation definition changed from @ServiceExtraMethod(value = org.openl.generated.services.ServiceExtraMethodHandler2Impl.class) to @ServiceExtraMethod(value = org.openl.generated.services.ServiceExtraMethodHandler2Impl) then the code is compiled successfully.

Why does the compilation start to fail with .class? I can't reproduce the same issue on IntelliJ IDEA.

Can you suggest what to try? Is it expected for Groovy to stop supporting .class in Groovy 4?