Add Events Firing for Phishing Detection Settings (duckduckgo#1012)

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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/0/72649045549333/1208270234071171/f
iOS PR: duckduckgo/iOS#3423
macOS PR: duckduckgo/macos-browser#3379
What kind of version bump will this require?:Minor

**Optional**:

Tech Design URL: N/A
CC:

**Description**:
In [✓ Phishing Detection
Pixels](https://app.asana.com/0/0/1207699541075655/f) we defined several
pixels to include, and one of them did not make it into the initial
release:
- macos.phishing-detection.feature-toggled:
  - Parameters:
    - newState - on/off, indicating whether the user turned it on or off
- Condition
  - triggers when a user disables the feature from the settings page
- Reasoning
- the aim is to use this as a "do-no-harm" KPI, to determine how many
users are actively choosing to disable/enable phishing protection

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**Steps to test this PR**:
1. Point to tespach/phish-det-settings-event
2. Build the macOS browser
3. Filter by `m_mac_phishing_detection_setting-toggled` in the debug
output of the app
4. Ensure you're authenticated via use-login.duckduckgo.com - this
feature is internal only
5. Go to Settings>General
6. Toggle "Malicious Site Protection"
7. Return to debug output and ensure you see:
8. `👾[Standard-Fired] m_mac_phishing_detection_setting-toggled
["appVersion": "1.109.0", "pixelSource": "browser-dmg",
"setting_toggled_to": "false"]`

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Using a simulator where a physical device is unavailable is acceptable.
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**OS Testing**:

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

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###### Internal references:
[Software Engineering
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Sources/PhishingDetection/PhishingDetectionEvents.swift

@@ -22,6 +22,7 @@ import PixelKit
 public extension PixelKit {
     enum Parameters: Hashable {
         public static let clientSideHit = "client_side_hit"
+        public static let settingToggledTo = "setting_toggled_to"
     }
 }
 
@@ -30,6 +31,7 @@ public enum PhishingDetectionEvents: PixelKitEventV2 {
     case visitSite
     case iframeLoaded
     case updateTaskFailed48h(error: Error?)
+    case settingToggled(to: Bool)
 
     public var name: String {
         switch self {
@@ -41,6 +43,8 @@ public enum PhishingDetectionEvents: PixelKitEventV2 {
             return "phishing_detection_iframe-loaded"
         case .updateTaskFailed48h:
             return "phishing_detection_update-task-failed-48h"
+        case .settingToggled:
+            return "phishing_detection_setting-toggled"
         }
     }
 
@@ -54,6 +58,8 @@ public enum PhishingDetectionEvents: PixelKitEventV2 {
             return [:]
         case .updateTaskFailed48h(let error):
             return error?.pixelParameters
+        case .settingToggled(let state):
+            return [PixelKit.Parameters.settingToggledTo: String(state)]
         }
     }
 
@@ -67,6 +73,8 @@ public enum PhishingDetectionEvents: PixelKitEventV2 {
             return nil
         case .iframeLoaded:
             return nil
+        case .settingToggled:
+            return nil
         }
     }