Remove autofill survey (#2819)

Task/Issue URL:
https://app.asana.com/0/1187352151074490/1207364165261200/f
Tech Design URL:
CC:

**Description**:
Remove the autofill survey but not all associated code (e.g. the
persisted flag), since I have zero context there.

**Steps to test this PR**:
1. On main, go to Settings > Passwords and confirm the survey prompt is
visible
2. Do likewise on this branch and confirm it isn't.

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DuckDuckGo/Preferences/View/PreferencesAutofillView.swift

@@ -68,42 +68,6 @@ extension Preferences {
                 // Autofill Content  Button
                 PreferencePaneSection {
 
-                    // New section
-                    if model.autofillSurveyEnabled {
-                        HStack(alignment: .top, spacing: 20) {
-                            Image(.passwordsDDG128)
-                                .frame(width: 64, height: 48)
-
-                            VStack(alignment: .leading) {
-                                Text(verbatim: "Help us improve!")
-                                    .bold()
-                                Text(verbatim: "We want to make using passwords in DuckDuckGo better.")
-                                    .foregroundColor(.greyText)
-                                    .padding(.top, 1)
-
-                                HStack {
-                                    Button(action: {
-                                        model.disableAutofillSurvey()
-                                    }, label: {
-                                        Text(verbatim: "No Thanks")
-                                    })
-                                    Button(action: {
-                                        model.launchSurvey()
-                                    }, label: {
-                                        Text(verbatim: "Take Survey")
-                                    })
-                                    .buttonStyle(DefaultActionButtonStyle(enabled: true))
-                                }
-                                .padding(.top, 12)
-                            }
-
-                            Spacer()
-                        }
-                        .padding()
-                        .roundedBorder()
-                        .padding(.bottom, 24)
-                    }
-
                     Button(UserText.autofillViewContentButton) {
                         model.showAutofillPopover()
                     }