Extend validity period for user counts to 24 hours [RUN ALL RSPEC] [RUN AS-IF-FOSS]

What does this MR do?

Some further analysis in #325458 (comment 534771603)

20 minutes is a very short validity period for these counts. Personal projects are at 24 hours already, but I feel like these could even be a week or a month since cache invalidation for them is quite aggressive.

Let's start at 24 hours and see how we go. The goal is to make the underlying queries drop out of the top10, which is a frequency-related analysis, so this will hopefully do the trick.

Does this MR meet the acceptance criteria?

Conformity

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  • I have not included a changelog entry because this change is behind a feature flag
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Security

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Related to #325458 (closed)