Race Condition in LRU cache for references can lead to null references

[kafis]

Describe the bug
The referenceResolver does occasionally resolve references to null.

The problem is, that the code, when resolving does first check which elements are already in the cache. It then fetches the "not yet in the cache" items and puts them there. This operation drops LRU items. Code still thinks that all items are in the cache and retrieves the references from the cache unchecked. Leading to null.

The symptom can be observed in SUPPORT-33245

To Reproduce
Steps to reproduce the behavior:

1. Call method with params
2. See error

Expected behavior
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Additional context
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