Fix verbose .env file missing

Changed:
- `logger.info()` -> `logger.warning()` to output a warning as it should if the .env file is missing.

src/dotenv/main.py

@@ -58,7 +58,7 @@ def _get_stream(self) -> Iterator[IO[str]]:
             yield self.stream
         else:
             if self.verbose:
-                logger.info(
+                logger.warning(
                     "Python-dotenv could not find configuration file %s.",
                     self.dotenv_path or '.env',
                 )