chore: Upgrade pmd-apex to v6.35.0

What does this MR do?

Fixes AST traversal bug in pmd rules where visitor does not properly descend into child nodes.

What are the relevant issue numbers?

https://gitlab.com/gitlab-org/security-products/release/-/issues/111

Does this MR meet the acceptance criteria?

• Changelog entry added
• Documentation created/updated for GitLab EE, if necessary
• Documentation created/updated for this project, if necessary
• Documentation reviewed by technical writer or follow-up review issue created
• Tests added for this feature/bug
• Job definition updated, if necessary
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  • Job definition example
  • CI Templates
• Conforms to the code review guidelines
• Conforms to the Go guidelines
• Security reports checked/validated by reviewer