fix(dw_base): env_loader 兼容 Python 3.6（capture_output → stdout/stderr PIPE）

dw_base/utils/env_loader.py

@@ -15,7 +15,7 @@ def bootstrap_env(env_sh_path: str = None) -> None:
         env_sh_path = str(project_root / 'conf' / 'env.sh')
     result = subprocess.run(
         ['bash', '-c', f'. "{env_sh_path}" && env -0'],
-        capture_output=True, check=True,
+        stdout=subprocess.PIPE, stderr=subprocess.PIPE, check=True,
     )
     for entry in result.stdout.split(b'\x00'):
         if not entry: