TST: Update Python versions in CI
TST: Update Python versions in CI

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