Update app/content_service/get_lecture_from_artemis.py

Co-authored-by: coderabbitai[bot] <136622811+coderabbitai[bot]@users.noreply.github.com>

app/content_service/get_lecture_from_artemis.py

@@ -11,11 +11,10 @@ def download_lecture_pdf(base_url: str, unit_id: int) -> tempfile.NamedTemporary
     artemis_url = f"{base_url}/api/v1/public/pyris/data/lecture-units/{unit_id}/pdf"
     response = requests.get(artemis_url, stream=True)
     if response.status_code != 200:
-        print(f"Failed to download the file. Status code: {response.status_code}")
-        raise ConnectionError
+        raise ConnectionError(f"Failed to download the file. Status code: {response.status_code}, URL: {artemis_url}")
 
-    temp_file = tempfile.NamedTemporaryFile()
-    for chunk in response.iter_content(chunk_size=DOWNLOAD_BUFFER_SIZE):
-        if chunk:
-            temp_file.write(chunk)
-    return temp_file
+    with tempfile.NamedTemporaryFile() as temp_file:
+        for chunk in response.iter_content(chunk_size=DOWNLOAD_BUFFER_SIZE):
+            if chunk:
+                temp_file.write(chunk)
+        return temp_file