Fix autofill search authentication looping (#3598)

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Task/Issue URL:
https://app.asana.com/0/1203822806345703/1208755477452311/f
Tech Design URL:
CC:

**Description**:
Fixes an issue where if the Passwords screen is dismissed while in
search mode, UISearchController prevented the Passwords screen from
being released from memory. I’ve also found and fixed a memory leak with
the autofill breakage reporter.

DuckDuckGo/AutofillLoginSettingsListViewController.swift

@@ -228,6 +228,7 @@ final class AutofillLoginSettingsListViewController: UIViewController {
         super.viewDidLoad()
         title = UserText.autofillLoginListTitle
         extendedLayoutIncludesOpaqueBars = true
+        navigationController?.presentationController?.delegate = self
         setupCancellables()
         installSubviews()
         installConstraints()
@@ -449,6 +450,11 @@ final class AutofillLoginSettingsListViewController: UIViewController {
         }
     }
 
+    private func dismissSearchIfRequired() {
+        guard searchController.isActive else { return }
+        searchController.dismiss(animated: false)
+    }
+
     private func presentDeleteConfirmation(for title: String, domain: String) {
         let message = title.isEmpty ? UserText.autofillLoginListLoginDeletedToastMessageNoTitle
                                     : UserText.autofillLoginListLoginDeletedToastMessage(for: title)
@@ -805,11 +811,11 @@ final class AutofillLoginSettingsListViewController: UIViewController {
         let cell = tableView.dequeueCell(ofType: AutofillBreakageReportTableViewCell.self, for: indexPath)
         let contentView = AutofillBreakageReportCellContentView(onReport: { [weak self] in
 
-            guard let alert = self?.viewModel.createBreakageReporterAlert() else {
+            guard let self = self, let alert = self.viewModel.createBreakageReporterAlert() else {
                 return
             }
 
-            self?.present(controller: alert, fromView: tableView)
+            self.present(controller: alert, fromView: self.tableView)
 
             Pixel.fire(pixel: .autofillLoginsReportConfirmationPromptDisplayed)
         })
@@ -1125,6 +1131,16 @@ extension AutofillLoginSettingsListViewController: UISearchBarDelegate {
     }
 }
 
+// MARK: UIAdaptivePresentationControllerDelegate
+
+extension AutofillLoginSettingsListViewController: UIAdaptivePresentationControllerDelegate {
+
+    func presentationControllerDidDismiss(_ presentationController: UIPresentationController) {
+        dismissSearchIfRequired()
+    }
+
+}
+
 // MARK: Keyboard
 
 extension AutofillLoginSettingsListViewController {