Clarifying support of feature flags and features behind them

What does this MR do?

The text concerning feature flags and the functionality behind them is confusing. When a feature flag is defaulted on for SaaS and self-managed, the functionality behind the flag will be available for Dedicated. The old text made it sound like the feature wouldn't be available until the feature flag was completely removed from the code. The updated text makes it more clear about what is available and what isn't.

Related issues

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