Add condition for warning notice

Author: mofeing

test/runtests.jl

@@ -73,7 +73,7 @@ if TENET_TEST_GROUP == "all" || TENET_TEST_GROUP == "integration"
     end
 end
 
-if TENET_TEST_GROUP == "all"
+if TENET_TEST_GROUP == "all" || TENET_TEST_GROUP == "python"
     @warn """
         Python tests have been moved to their own folder.
         You must call `julia --project=test/python test/python/runtests.jl` to run them.