Replace nativeJetpackSetupFlow feature flag with AB testing enum case.

Author: selanthiraiyan

Experiments/Experiments/DefaultFeatureFlagService.swift

@@ -49,8 +49,6 @@ public struct DefaultFeatureFlagService: FeatureFlagService {
                 .performanceMonitoringUserInteraction:
             // Disabled by default to avoid costs spikes, unless in internal testing builds.
             return buildConfig == .alpha
-        case .nativeJetpackSetupFlow:
-            return buildConfig == .localDeveloper || buildConfig == .alpha
         case .analyticsHub:
             return buildConfig == .localDeveloper || buildConfig == .alpha
         default:

WooCommerce/Classes/Authentication/AuthenticationManager.swift

@@ -755,8 +755,7 @@ private extension AuthenticationManager {
         }
 
         // Shows the native Jetpack flow during the site discovery flow.
-        // TODO-8075: replace feature flag with A/B testing
-        if featureFlagService.isFeatureFlagEnabled(.nativeJetpackSetupFlow) {
+        if ABTest.abTestNativeJetpackSetupFlow.variation == .control {
             return jetpackSetupUI(for: site.url,
                                   connectionMissingOnly: site.hasJetpack && site.isJetpackActive,
                                   in: navigationController)