Make env var default param declaration os invariant

Author: jnccd

src/super_gradients/common/environment/env_variables.py

@@ -48,7 +48,7 @@ def HYDRA_FULL_ERROR(self, value: str):
 
     @property
     def SUPER_GRADIENTS_LOG_DIR(self) -> str:
-        return os.getenv("SUPER_GRADIENTS_LOG_DIR", default=f"{Path.home()}/sg_logs")
+        return os.getenv("SUPER_GRADIENTS_LOG_DIR", default=str(Path.home()/"sg_logs"))
 
 
 env_variables = EnvironmentVariables()