test: expect newline between heading and body in trafilatura output

trafilatura 2.3 (bumped in #421) separates an <h1> from the following
paragraph with a newline; 2.2 glued them together ("Example TitleThis is
..."). test_networkidle_timeout_still_extracts_content pinned the old
glued string, so the Docker test stage has failed on every main run since
#421 merged.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

tests/owui_test.py

@@ -99,7 +99,7 @@ async def test_networkidle_timeout_still_extracts_content():
         LoadRequest(urls=["https://example.test"]), None, fake_dep()
     )
     assert results[0].page_content == (
-        "Example TitleThis is the main article body with enough words for "
+        "Example Title\nThis is the main article body with enough words for "
         "trafilatura to consider it real content rather than boilerplate."
     )