Use correct cursor pattern

What does this MR do and why?

Use correct cursor pattern

This commit fixes cursor for keyset pagination in groups and projects audit event finder

EE: true Changelog: added

References

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Before	After

How to set up and validate locally

1. Disable Feature.disable(:read_audit_events_from_new_tables)
2. Call audit events API: base_url/api/v4/groups/flightjs/audit_events?pagination=keyset&per_page=1
3. Get next page link from response headers
4. Enable Feature.enable(:read_audit_events_from_new_tables)
5. Call API via next page link
6. Check error: RuntimeError (Incorrect cursor values were given. Missing items: created_at):

To solve this we need to exclude created_at in order_by clause when using keyset pagination.

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Related to #493723