fix: isFeatureEnabled wasn't sending the $feature_flag_called event

[marandaneto]

💡 Motivation and Context

Closes https://posthoghelp.zendesk.com/agent/tickets/18551

💚 How did you test it?

📝 Checklist

• I reviewed the submitted code.
• I added tests to verify the changes.
• I updated the docs if needed.
• No breaking change or entry added to the changelog.

[neilkakkar]

in most SDKs isFeatureEnabled calls getFeatureFlag, so all of this handling can be in one place. Think we can do the same here?

[marandaneto]

because of this tiny bit of code its trickier

posthog-android/posthog/src/main/java/com/posthog/internal/PostHogFeatureFlags.kt

Lines 205 to 214 in 3a0ede8

	return if (value != null) {
	if (value is Boolean) {
	value
	} else {
	// if its multivariant flag, its enabled by default
	true
	}
	} else {
	defaultValue
	}

since this is a compiled language and it has strongly typed methods, will get it merged for now and think if its worth the refactoring 🧐