Describe the bug

Found in e2e run https://public-prow.kcp.k8c.io/view/s3/prow-public-data/pr-logs/pull/kcp-dev_kcp/4027/pull-kcp-test-e2e/2043985938412998656

Steps To Reproduce

N/A

Expected Behaviour

Don't modify objects in cache.

Additional Context

No response