Second macOS CPM experiment (#1017)

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Please review the release process for BrowserServicesKit
[here](https://app.asana.com/0/1200194497630846/1200837094583426).

**Required**:

Task/Issue URL:
https://app.asana.com/0/1205142657210376/1208488711477099/f
iOS PR: 
macOS PR: duckduckgo/macos-browser#3397
What kind of version bump will this require?: Major/Minor/Patch

**Optional**:

Tech Design URL:
https://app.asana.com/0/1205142657210376/1208527766092596/f
CC: @ayoy

**Description**:

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This PR cleans up the previous experiment (#937), and creates a new
subfeature for the new experiment. The experiment logic will be in the
macOS PR.

**Steps to test this PR**:
1.
1.

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you expect the reviewer to test, then delete configurations you *know*
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**OS Testing**:

* [ ] iOS 14
* [ ] iOS 15
* [ ] iOS 16
* [ ] macOS 10.15
* [ ] macOS 11
* [ ] macOS 12

---
###### Internal references:
[Software Engineering
Expectations](https://app.asana.com/0/59792373528535/199064865822552)
[Technical Design
Template](https://app.asana.com/0/59792373528535/184709971311943)

Sources/BrowserServicesKit/ContentBlocking/AdClickAttribution/AdClickAttributionDetection.swift

@@ -42,20 +42,17 @@ public class AdClickAttributionDetection {
     private let tld: TLD
     private let eventReporting: EventMapping<AdClickAttributionEvents>?
     private let errorReporting: EventMapping<AdClickAttributionDebugEvents>?
-    private let cpmExperimentOn: Bool?
 
     public weak var delegate: AdClickAttributionDetectionDelegate?
 
     public init(feature: AdClickAttributing,
                 tld: TLD,
                 eventReporting: EventMapping<AdClickAttributionEvents>? = nil,
-                errorReporting: EventMapping<AdClickAttributionDebugEvents>? = nil,
-                cpmExperimentOn: Bool? = nil) {
+                errorReporting: EventMapping<AdClickAttributionDebugEvents>? = nil) {
         self.attributionFeature = feature
         self.tld = tld
         self.eventReporting = eventReporting
         self.errorReporting = errorReporting
-        self.cpmExperimentOn = cpmExperimentOn
     }
 
     // MARK: - Public API
@@ -146,12 +143,9 @@ public class AdClickAttributionDetection {
             domainDetection = "none"
         }
 
-        var parameters = [AdClickAttributionEvents.Parameters.domainDetection: domainDetection,
+        let parameters = [AdClickAttributionEvents.Parameters.domainDetection: domainDetection,
                           AdClickAttributionEvents.Parameters.domainDetectionEnabled: attributionFeature.isDomainDetectionEnabled ? "1" : "0",
                           AdClickAttributionEvents.Parameters.heuristicDetectionEnabled: attributionFeature.isHeuristicDetectionEnabled ? "1" : "0"]
-        if let cpmExperimentOn {
-            parameters[AdClickAttributionEvents.Parameters.cpmExperiment] = cpmExperimentOn ? "1" : "0"
-        }
         eventReporting?.fire(.adAttributionDetected, parameters: parameters)
     }
 }

Sources/BrowserServicesKit/ContentBlocking/AdClickAttribution/AdClickAttributionEvents.swift

@@ -25,7 +25,6 @@ public enum AdClickAttributionEvents {
         public static let heuristicDetectionEnabled = "heuristicDetectionEnabled"
         public static let domainDetectionEnabled = "domainDetectionEnabled"
         public static let count = "count"
-        public static let cpmExperiment = "cpmExperiment"
     }
 
     case adAttributionDetected

Sources/BrowserServicesKit/ContentBlocking/AdClickAttribution/AdClickAttributionLogic.swift

@@ -207,15 +207,11 @@ public class AdClickAttributionLogic {
         }
     }
 
-    public func onRequestDetected(request: DetectedRequest, cpmExperimentOn: Bool? = nil) {
+    public func onRequestDetected(request: DetectedRequest) {
         guard registerFirstActivity,
             BlockingState.allowed(reason: .adClickAttribution) == request.state else { return }
 
-        var parameters: [String: String] = [:]
-        if let cpmExperimentOn {
-            parameters[AdClickAttributionEvents.Parameters.cpmExperiment] = cpmExperimentOn ? "1" : "0"
-        }
-        eventReporting?.fire(.adAttributionActive, parameters: parameters)
+        eventReporting?.fire(.adAttributionActive)
         registerFirstActivity = false
     }
 

Sources/BrowserServicesKit/PrivacyConfig/Features/PrivacyFeature.swift

@@ -123,7 +123,7 @@ public enum AutoconsentSubfeature: String, PrivacySubfeature {
     }
 
     case onByDefault
-    case filterlistExperiment
+    case filterlistExperiment2
 }
 
 public enum PrivacyProSubfeature: String, Equatable, PrivacySubfeature {