fix: remove unnecessary pragma on now-covered exception handler

The SSE stream disconnect test now exercises this code path, making
the pragma: no cover annotation invalid per strict-no-cover.

Github-Issue:#1811

Author: skyvanguard

src/mcp/client/streamable_http.py

@@ -334,7 +334,7 @@ async def _handle_sse_response(
                     await response.aclose()
                     return  # Normal completion, no reconnect needed
         except Exception as e:
-            logger.debug(f"SSE stream ended: {e}")  # pragma: no cover
+            logger.debug(f"SSE stream ended: {e}")
 
         # Stream ended without response - reconnect if we received an event with ID
         if last_event_id is not None: