Fix a few typos in microversion doc
Fix a few typos in microversion doc

Patch I29ab6f625df59ba3732f9730a610e14dfe6094ea already fixed some
comments for the doc. But there are still some typos that need to
be fixed. This patch is to fix those.

Change-Id: I6ab6eabfb0faf28e175179c0097e196c4fa944ea

Tesora/tesora-tempest,Tesora/tesora-tempest,sebrandon1/tempest,cisco-openstack/tempest,Juniper/tempest,bigswitch/tempest,LIS/lis-tempest,LIS/lis-tempest,openstack/tempest,masayukig/tempest,zsoltdudas/lis-tempest,bigswitch/tempest,masayukig/tempest,openstack/tempest,sebrandon1/tempest,Juniper/tempest,zsoltdudas/lis-tempest,cisco-openstack/tempest,vedujoshi/tempest,vedujoshi/tempest