Make the iOS Webview e2e test more resilient (mobile-dev-inc#2920)

Author: Fishbowler

e2e/workspaces/simple_web_view/webview.yaml

@@ -8,6 +8,9 @@ tags:
 
 - tapOn: Open Login Page
 
-- assertVisible: Login
+- extendedWaitUntil:
+    visible: Login
+    timeout: 30000
+    label: Wait for Login page to load
 - assertVisible: Sign In
 - assertVisible: Forgot your password?