TF-3260 Add integration test for app grid

Signed-off-by: dab246 <tdvu@linagora.com>

integration_test/robots/app_grid_robot.dart

@@ -0,0 +1,12 @@
+
+import 'package:flutter_test/flutter_test.dart';
+
+import '../base/core_robot.dart';
+
+class AppGridRobot extends CoreRobot {
+  AppGridRobot(super.$);
+
+  Future<void> openAppInAppGridByAppName(String appName) async {
+    await $(find.text(appName)).tap();
+  }
+}

integration_test/robots/mailbox_menu_robot.dart

@@ -0,0 +1,10 @@
+
+import '../base/core_robot.dart';
+
+class MailboxMenuRobot extends CoreRobot {
+  MailboxMenuRobot(super.$);
+
+  Future<void> openAppGrid() async {
+    await $(#toggle_app_grid_button).tap();
+  }
+}

integration_test/robots/thread_robot.dart

@@ -20,14 +20,12 @@ class ThreadRobot extends CoreRobot {
     await $(ThreadView).$(SearchBarView).tap();
   }
 
-  Future<void> openMailbox(String mailboxName) async {
-    await $(#mobile_mailbox_menu_button).tap();
-    await $.scrollUntilVisible(finder: $(mailboxName));
-    await $(mailboxName).tap();
-  }
-
   Future<void> openEmailWithSubject(String subject) async {
     await $.scrollUntilVisible(finder: $(subject));
     await $(subject).tap();
   }
+
+  Future<void> openMailbox() async {
+    await $(#mobile_mailbox_menu_button).tap();
+  }
 }