Ensure maestro test works with and without gesture navigation (#5350)

Task/Issue URL:
https://app.asana.com/0/488551667048375/1208915665635635/f

### Description
Simplifies a UI test which currently kills the app by activating
multi-tasking view and swiping the app away. Replaces with a method
which also works with gesture navigation.

### Steps to test this PR
- qa optional
- [optional] run
`.maestro/privacy_tests/7_-_Browser_restart_mid-session.yaml` where
gesture navigation on and off (e.g., on emulators running API 30 and API
34 which have different nav behaviours by default)

Co-authored-by: Craig Russell <[email protected]>

.maestro/privacy_tests/7_-_Browser_restart_mid-session.yaml

@@ -91,11 +91,7 @@ tags:
     text: "convert.ad-company.site"
 - action: back
 - action: back
-- tapOn:
-    id: "com.android.systemui:id/recent_apps"
-- swipe:
-    start: 100,500
-    end: 100,200
+- killApp
 - launchApp:
     clearState: false
 - assertVisible: