tempest: Fix qos extension check

Fix issues introduced by the recent change. [1]

[1] I88e59cdbd79afb5337052ba3e5aecb96c7c8ea1c

Closes-Bug: #1649171
Change-Id: I2a2b627fd30ec564d8c8566fd3e46eb889e15dc9
2 files changed
tree: 75be8230b349e06b14f8cbf5983569c0b14394ee
  1. neutron/