This precludes us from landing anything in the gate, because we
treat Sphinx warnings as errors in OpenStack.
Specifically, 3 warnings are fixed:
/home/zuul/src/opendev.org/openstack/swift/swift/common/middleware\
/s3api/etree.py:docstring of\
swift.common.middleware.s3api.etree.Element:1:\
Inline strong start-string without end-string.
duplicate object description of\
swift.common.middleware.versioned_writes, other instance in\
middleware, use :noindex: for one of them
duplicate object description of\
swift.common.ring.composite_builder, other instance in\
overview_ring, use :noindex: for one of them
Change-Id: I5e0bd61a301d46b2674b4605882462575b635220
eaf180c68d