Added conftest foo to protect against asdf 3.0.0
Added conftest foo to protect against asdf 3.0.0

mhvk/astropy,astropy/astropy,astropy/astropy,pllim/astropy,lpsinger/astropy,mhvk/astropy,mhvk/astropy,saimn/astropy,saimn/astropy,pllim/astropy,mhvk/astropy,pllim/astropy,saimn/astropy,lpsinger/astropy,StuartLittlefair/astropy,astropy/astropy,lpsinger/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,larrybradley/astropy,astropy/astropy,StuartLittlefair/astropy,larrybradley/astropy,mhvk/astropy,larrybradley/astropy,saimn/astropy,StuartLittlefair/astropy,pllim/astropy,lpsinger/astropy,astropy/astropy,saimn/astropy,pllim/astropy,larrybradley/astropy,lpsinger/astropy,larrybradley/astropy