Add UI Test for WebView state restoration (#3920)

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Task/Issue URL:
https://app.asana.com/0/1206226850447395/1208991633646642
Tech Design URL:
CC:

**Description**:

Adds UI test for WebView state restoration.

**Steps to test this PR**:
1. Make sure UI test is passing
(`browser_features/state_restoration.yaml`).

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you expect the reviewer to test, then delete configurations you *know*
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**Definition of Done (Internal Only)**:

* [x] Does this PR satisfy our [Definition of
Done](https://app.asana.com/0/1202500774821704/1207634633537039/f)?

---
###### Internal references:
[Software Engineering
Expectations](https://app.asana.com/0/59792373528535/199064865822552)
[Technical Design
Template](https://app.asana.com/0/59792373528535/184709971311943)

.maestro/browser_features/state_restoration.yaml

@@ -0,0 +1,53 @@
+# state_restoration.yaml
+appId: com.duckduckgo.mobile.ios
+tags:
+    - release
+
+---
+
+# Set up 
+- runFlow: 
+    file: ../shared/setup.yaml
+
+# Load Site
+- assertVisible:
+    id: "searchEntry"
+- tapOn:
+    id: "searchEntry"
+- inputText: "https://www.wikipedia.org/"
+- pressKey: Enter
+
+# Create navigation stack
+- assertVisible: "English"
+- tapOn: "English"
+- assertVisible: "Welcome to Wikipedia.*"
+- tapOn: "Wikipedia" 
+- assertVisible: "Article"
+- scrollUntilVisible:
+    element: "United States"
+# Make sure bottom bar is visible
+- tapOn:
+    point: 80%, 99%
+- tapOn: "Browse Back"
+- assertVisible: "Welcome to Wikipedia.*"
+
+# Load a new tab
+- longPressOn: "Tab Switcher"
+- assertVisible:
+    id: "searchEntry"
+- tapOn: 
+    id: "searchEntry"
+- inputText: "https://example.com"
+- pressKey: Enter
+
+- stopApp
+- launchApp
+
+- tapOn: "Tab Switcher"
+- tapOn:
+    point: 20%, 25%
+
+# Check if state from previous session was restored
+- assertVisible: "Welcome to Wikipedia.*"
+- tapOn: "Browse Forward"
+- assertVisible: "United States"