Re-order test-requirements.txt
Re-order test-requirements.txt

tox fails when Sphinx is installed before fuel-plugin-builder. There's
probably a missing requirement somewhere but reverting the list fixes
the issue for now.

Change-Id: I770f0cfa477d909466176f9df604fe5058dd48b5

stackforge/fuel-plugin-elasticsearch-kibana,stackforge/fuel-plugin-elasticsearch-kibana,stackforge/fuel-plugin-elasticsearch-kibana