add indent for availability

Author: pxinwr

Doc/library/netrc.rst

@@ -15,7 +15,7 @@
 This module implements an object-oriented interface to :file:`.netrc` files.
 
 .. availability:: Unix. VxWorks has no user home directory so it doesn't support ftp
-auto-login. This module is not supported on VxWorks.
+   auto-login. This module is not supported on VxWorks.
 
 The :class:`~netrc.netrc` class parses and encapsulates the netrc file format used by
 the Unix :program:`ftp` program and other FTP clients.