fix(test): stop hardcoding brand source_urls in integration test

Brand source_urls grow as verification backfills add references
(e.g. Wikidata); assert membership instead of exact list equality.

Author: Seungpyo1007

tests/integration/test_brands.py

@@ -17,7 +17,7 @@ def test_get_brand_detail(client: TestClient) -> None:
     assert body["slug"] == "samsung"
     assert body["country"] == "KR"
     assert body["url"] == "/v1/brands/samsung"
-    assert body["source_urls"] == ["https://www.samsung.com"]
+    assert "https://www.samsung.com" in body["source_urls"]
 
 
 def test_unknown_brand_returns_404_envelope(client: TestClient) -> None: