test: Avocado tests default to run on fedora-24
test: Avocado tests default to run on fedora-24

The Avocado tests only run on fedora-24. Work to move them
to a later version of Fedora has not yet been done.

Closes #7078
cockpituous/cockpit,xhad/cockpit,larskarlitski/cockpit,mareklibra/cockpit,stefwalter/cockpit,deryni/cockpit,larskarlitski/cockpit,Scribery/cockpit,deryni/cockpit,moraleslazaro/cockpit,cockpituous/cockpit,mvollmer/cockpit,cockpit-project/cockpit,larskarlitski/cockpit,mareklibra/cockpit,stefwalter/cockpit,andreasn/cockpit,stefwalter/cockpit,Scribery/cockpit,cockpituous/cockpit,martinpitt/cockpit,michalskrivanek/cockpit,Scribery/cockpit,petervo/cockpit,martinpitt/cockpit,petervo/cockpit,larskarlitski/cockpit,michalskrivanek/cockpit,larsu/cockpit,moraleslazaro/cockpit,harishanand95/cockpit,deryni/cockpit,michalskrivanek/cockpit,SotolitoLabs/cockpit,larsu/cockpit,SotolitoLabs/cockpit,cockpit-project/cockpit,larskarlitski/cockpit,petervo/cockpit,garrett/cockpit,cockpituous/cockpit,cockpit-project/cockpit,harishanand95/cockpit,stefwalter/cockpit,xhad/cockpit,stefwalter/cockpit,petervo/cockpit,moraleslazaro/cockpit,mareklibra/cockpit,andreasn/cockpit,harishanand95/cockpit,xhad/cockpit,michalskrivanek/cockpit,mvollmer/cockpit,SotolitoLabs/cockpit,andreasn/cockpit,harishanand95/cockpit,xhad/cockpit,xhad/cockpit,andreasn/cockpit,garrett/cockpit,larskarlitski/cockpit,mvollmer/cockpit,larsu/cockpit,deryni/cockpit,harishanand95/cockpit,Scribery/cockpit,martinpitt/cockpit,petervo/cockpit,mvollmer/cockpit,moraleslazaro/cockpit,moraleslazaro/cockpit,mvollmer/cockpit,stefwalter/cockpit,martinpitt/cockpit,mareklibra/cockpit,SotolitoLabs/cockpit,moraleslazaro/cockpit,cockpit-project/cockpit,cockpituous/cockpit,michalskrivanek/cockpit,larsu/cockpit,andreasn/cockpit,michalskrivanek/cockpit,andreasn/cockpit,harishanand95/cockpit,Scribery/cockpit,garrett/cockpit,xhad/cockpit,larsu/cockpit,SotolitoLabs/cockpit,xhad/cockpit,petervo/cockpit,garrett/cockpit,deryni/cockpit,Scribery/cockpit,deryni/cockpit,Scribery/cockpit,garrett/cockpit,moraleslazaro/cockpit,petervo/cockpit,stefwalter/cockpit,mareklibra/cockpit,SotolitoLabs/cockpit,mareklibra/cockpit,michalskrivanek/cockpit,martinpitt/cockpit,SotolitoLabs/cockpit,andreasn/cockpit,mareklibra/cockpit,cockpit-project/cockpit,larsu/cockpit,larskarlitski/cockpit,harishanand95/cockpit,deryni/cockpit,cockpituous/cockpit