nixos/tests/freetube: fix ocr

- change text that is waited for on preferences page, as previous one
stopped being recognized by OCR on xorg after freetube update to 0.21.0
- increase timeout from 30 sec to 60 sec as OCR is sometimes slow

nixos/tests/freetube.nix

@@ -35,7 +35,7 @@ let
         machine.wait_for_text('Your Subscription list is currently empty')
         machine.screenshot("main.png")
         machine.send_key("ctrl-comma")
-        machine.wait_for_text('General Settings', timeout=30)
+        machine.wait_for_text('Data Settings', timeout=60)
         machine.screenshot("preferences.png")
       '';
     });