Consider flags enabled when generating GraphQL schema

What does this MR do?

!25172 (merged) fixed issue where a developer could generate docs different than what is generated in CI.

With the !26378 (merged), the upgrade to graphql gem 1.9.19 fixes an issue where the visibilty? of a field was not handled correctly. Since we check the feature flag for field visibility, feature flag controlled fields are no longer generated when the schema is output.

Now force enable the feature flags to properly document all fields.

Related to #207278 (closed)

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Does this MR meet the acceptance criteria?

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