ref(project): use hasFlags flag for CTA check

[michellewzhang]

use the newly implemented hasFlags project flag as the final layer to determine whether the CTA should be shown.

TLDR: the CTA only shows up if... project has never sent flags before, event.contexts.flags is undefined, the platform is correct, & the org is under the cta flag.

const showCTA =
    !project.hasFlags &&
    !hasFlagContext &&
    featureFlagOnboardingPlatforms.includes(project.platform ?? 'other') &&
    organization.features.includes('feature-flag-cta');

here are the following possible code paths (all are tested)

event.contexts.flags = [ ... ] -> flag table rendered

event.contexts.flags = [ ] -> empty state

event.contexts.flags = undefined and hasFlags = true -> empty state

event.contexts.flags = undefined and hasFlags = false and feature-flag-cta = true and platform in [javascript, python] -> CTA shown

event.contexts.flags = undefined and feature-flag-cta = true and platform !in [javascript, python] -> section hidden

event.contexts.flags = undefined and feature-flag-cta = false -> section hidden