Seperate CUI url paths and tests (#6543)

* move CUI JS files to CUI url section

* add flag to seperate CUI code and tests

* re-enable tests

* move urls back to backend patterns

* swap switch logic

* fix merge

* returning PUI paths if CUI not enabled

* revert test changes

* fix plugin settings url

* URL is not dependant on UI generation

* small fixes

Co-authored-by: Oliver <oliver.henry.walters@gmail.com>

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Co-authored-by: Oliver <oliver.henry.walters@gmail.com>

InvenTree/label/tests.py

@@ -142,7 +142,8 @@ class LabelTest(InvenTreeAPITestCase):
         # Test that each element has been rendered correctly
         self.assertIn(f'part: {part_pk} - {part_name}', content)
         self.assertIn(f'data: {{"part": {part_pk}}}', content)
-        self.assertIn(f'http://testserver/part/{part_pk}/', content)
+        if settings.ENABLE_CLASSIC_FRONTEND:
+            self.assertIn(f'http://testserver/part/{part_pk}/', content)
 
         # Check that a encoded image has been generated
         self.assertIn('data:image/png;charset=utf-8;base64,', content)