fixing issue for python 3.8

Signed-off-by: DONNOT Benjamin <[email protected]>

Author: BDonnot

setup.py

@@ -32,6 +32,7 @@ def my_test_suite():
         "requests>=2.23.0",
         "packaging",  # because gym changes the way it uses numpy prng in version 0.26 and i need both gym before and after...
         "typing_extensions",
+        "orderly_set<5.4.0; python_version<='3.8'"
     ],
     "extras": {
         "optional": [