Add PyPi link to readme.rst

Change-Id: I73da9d013a54d3730a9edde33271cb1a1fca481a

README.rst

@@ -33,6 +33,7 @@ Project resources
 
 * Documentation: https://docs.openstack.org/python-ironicclient/latest/
 * Source: https://opendev.org/openstack/python-ironicclient
+* PyPi: https://pypi.org/project/python-ironicclient
 * Bugs: https://storyboard.openstack.org/#!/project/959
 * Release notes: https://docs.openstack.org/releasenotes/python-ironicclient/