update astropy data link

Author: jmbhughes

README.md

@@ -62,7 +62,7 @@ julia> result = reproject(input_data, output_projection, shape_out = (1000,1000)
 
 <img name="community" src="Images/output.png"/>
 
-Test files can be obtained from [here](https://astropy.stsci.edu/data/).
+Test files can be obtained from [here](https://www.astropy.org/astropy-data/).
 
 Related Packages
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