[Fix] Send stderr to subprocess.PIPE (#740)

mmengine/utils/version_utils.py

@@ -58,8 +58,9 @@ def _minimal_ext_cmd(cmd):
     env['LANGUAGE'] = 'C'
     env['LANG'] = 'C'
     env['LC_ALL'] = 'C'
-    out = subprocess.Popen(
-        cmd, stdout=subprocess.PIPE, env=env).communicate()[0]
+    out, err = subprocess.Popen(
+        cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE,
+        env=env).communicate()
     return out