logger.py: Fix resource leak (#2215)

opendevin/core/logger.py

@@ -216,7 +216,7 @@ class LlmFileHandler(logging.FileHandler):
         self.baseFilename = os.path.join(self.log_directory, filename)
         self.stream = self._open()
         super().emit(record)
-        self.stream.close
+        self.stream.close()
         opendevin_logger.debug('Logging to %s', self.baseFilename)
         self.message_counter += 1