disable contextual onboarding (#3667)

Task/Issue URL: https://app.asana.com/0/0/1208965309086157/f

**Description**: We want to disable the contextual onboarding while
leaving the rest of the treatment variant

DuckDuckGo/Statistics/Experiment/PixelExperiment.swift

@@ -60,8 +60,8 @@ enum PixelExperiment: String, CaseIterable {
 
     // These are the variants. Rename or add/remove them as needed.  If you change the string value
     //  remember to keep it clear for privacy triage.
-    case control = "oc"
-    case newOnboarding = "od"
+    case control = "oe"
+    case newOnboarding = "of"
 }
 
 // These functions contain the business logic for determining if the pixel should be fired or not.

DuckDuckGo/Tab/Model/Tab.swift

@@ -793,7 +793,6 @@ protocol NewWindowPolicyDecisionMaker {
 #endif
 
         if PixelExperiment.cohort == .newOnboarding {
-            Application.appDelegate.onboardingStateMachine.state = .notStarted
             setContent(.onboarding)
         } else {
             setContent(.onboardingDeprecated)