[mod_random_image] - no need field cache

[alikon]

Pull Request for Issue #23162 .

Summary of Changes

removed field cache

Testing Instructions

module works as before

[ghost]

I have tested this item ✅ successfully on 7cb1ee2<

@alikon Thanks for PR.

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[Quy]

I have tested this item ✅ successfully on 7cb1ee2

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[Quy]

RTC

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