Fix extract_swift_flags.py
Fix extract_swift_flags.py

The renaming of the swift-conf-changes.xml in the openstack-manual
repository broke a test in the extract_swift_flags.py script. This patch
changes the test to make the script work again.

Change-Id: I71b6960801163c2d2c52253d0c9a45ec2bf02b0d

savinash47/openstack-doc-tools,savinash47/openstack-doc-tools,openstack/openstack-doc-tools,savinash47/openstack-doc-tools,openstack/openstack-doc-tools