Remove enable private search suggestions telemetry

app/metrics.yaml

@@ -1479,25 +1479,6 @@ preferences:
     notification_emails:
       - android-probes@mozilla.com
     expires: "2022-02-01"
-  private_search_suggestions:
-    type: boolean
-    description: >
-      Whether or not the user has enabled showing search suggestions
-      in private mode.
-      default: false (we prompt the user, asking them to make a selection)
-    send_in_pings:
-      - metrics
-    bugs:
-      - https://github.com/mozilla-mobile/fenix/issues/11118
-    data_reviews:
-      - https://github.com/mozilla-mobile/fenix/pull/11211
-      - https://github.com/mozilla-mobile/fenix/pull/15713#issuecomment-703972068
-      - https://github.com/mozilla-mobile/fenix/pull/19924#issuecomment-861423789
-    data_sensitivity:
-      - interaction
-    notification_emails:
-      - android-probes@mozilla.com
-    expires: "2021-08-01"
   toolbar_position_setting:
     type: string
     description: >

app/src/main/java/org/mozilla/fenix/FenixApplication.kt

@@ -638,7 +638,6 @@ open class FenixApplication : LocaleAwareApplication(), Provider {
             bookmarksSuggestion.set(settings.shouldShowBookmarkSuggestions)
             clipboardSuggestionsEnabled.set(settings.shouldShowClipboardSuggestions)
             searchShortcutsEnabled.set(settings.shouldShowSearchShortcuts)
-            privateSearchSuggestions.set(settings.shouldShowSearchSuggestionsInPrivate)
             voiceSearchEnabled.set(settings.shouldShowVoiceSearch)
             openLinksInAppEnabled.set(settings.openLinksInExternalApp)
             signedInSync.set(settings.signedInFxaAccount)