move imports to top of file in test_frames
move imports to top of file in test_frames

@mhvk
https://github.com/astropy/astropy/pull/10624#discussion_r480408131

Signed-off-by: Nathaniel Starkman <ac14c573519de521a9fc5a84607d51c0c956190b@protonmail.com>

mhvk/astropy,aleksandr-bakanov/astropy,lpsinger/astropy,mhvk/astropy,pllim/astropy,dhomeier/astropy,saimn/astropy,mhvk/astropy,aleksandr-bakanov/astropy,mhvk/astropy,saimn/astropy,astropy/astropy,larrybradley/astropy,lpsinger/astropy,StuartLittlefair/astropy,pllim/astropy,StuartLittlefair/astropy,StuartLittlefair/astropy,mhvk/astropy,StuartLittlefair/astropy,larrybradley/astropy,lpsinger/astropy,saimn/astropy,larrybradley/astropy,larrybradley/astropy,lpsinger/astropy,StuartLittlefair/astropy,dhomeier/astropy,pllim/astropy,saimn/astropy,lpsinger/astropy,aleksandr-bakanov/astropy,aleksandr-bakanov/astropy,dhomeier/astropy,pllim/astropy,saimn/astropy,astropy/astropy,astropy/astropy,astropy/astropy,dhomeier/astropy,astropy/astropy,larrybradley/astropy,dhomeier/astropy,pllim/astropy