TF-3514 Add integration test for reply email with content contain image base64

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

integration_test/robots/thread_robot.dart

@@ -23,7 +23,10 @@ class ThreadRobot extends CoreRobot {
   }
 
   Future<void> openEmailWithSubject(String subject) async {
-    await $(find.byType(EmailTileBuilder)).first.tap();
+    await $(find.byType(EmailTileBuilder))
+      .which<EmailTileBuilder>((view) => view.presentationEmail.subject == subject)
+      .first
+      .tap();
     await $.pump(const Duration(seconds: 2));
   }