Allow @ResourceLock on @ClassTemplate classes

[raccoonback]

Fixes #5155

This PR enables the use of @ResourceLock on classes annotated with @ClassTemplate.

Background

Currently, applying @ResourceLock to a @ClassTemplate class results in the following failure:

Dynamic test descriptors must not declare exclusive resources

This happens because ClassTemplateInvocationTestDescriptor#getExclusiveResources() returns a non-empty set, causing the invocation descriptor to report exclusive resources even though the enclosing ClassTemplateTestDescriptor already collects and exposes them at the class level.

Summary of Changes

• Override ClassTemplateInvocationTestDescriptor#getExclusiveResources() to always return an empty set.

  • Class-level exclusive resources are already managed by ClassTemplateTestDescriptor, so the invocation descriptor should not contribute additional exclusive resources.

• Add a dedicated test classTemplateWithResourceLockExecutesSuccessfully() to verify that:

  • A @ClassTemplate class annotated with @ResourceLock executes successfully.
  • Both test and container events complete without errors.

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Definition of Done

• There are no TODOs left in the code
• Method preconditions are checked and documented in the method's Javadoc
• Coding conventions (e.g. for logging) have been followed
• Change is covered by automated tests including corner cases, errors, and exception handling
• Public API has Javadoc and @API annotations
• Change is documented in the User Guide and Release Notes