fix(pydoc): specify -a to _comp_compgen_filedir

Author: akinomyoga

completions/pydoc

@@ -33,7 +33,7 @@ _comp_cmd_pydoc()
     COMPREPLY+=($(compgen -W \
         '$("$1" keywords topics | command sed -e /^Here/d)' -- "$cur"))
 
-    _comp_compgen_filedir py
+    _comp_compgen -a filedir py
 } &&
     complete -F _comp_cmd_pydoc pydoc pydoc3