Set FF validity_check_es_filter default true

🚨 DO NOT MERGE YET 🚨

Please do not merge until rollout is completed > [Feature flag] Rollout of of `validity_check_es... (#560433)

What does this MR do and why?

The roll out of this feature has started > #560433

This MR sets the FF validity_check_es_filter to default true. Enabling it by default for self managed users.

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Before	After

How to set up and validate locally

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Related to #560433