chore: remove testing non-working SystemRandom

This is merely testing Python internals and actually does nothing as
SystemRandom is instationated on import of the secrets module, so the
patching done in this test had no effect on the secrets.choice output.

Author: nijel

social_core/tests/test_storage.py

@@ -1,4 +1,3 @@
-import random
 import unittest
 
 from social_core.storage import (
@@ -189,14 +188,3 @@ def test_is_integrity_error(self) -> None:
 
     def test_random_string(self) -> None:
         self.assertTrue(isinstance(self.strategy.random_string(), str))
-
-    def test_random_string_without_systemrandom(self) -> None:
-        def SystemRandom():
-            raise NotImplementedError
-
-        orig_random = getattr(random, "SystemRandom", None)
-        random.SystemRandom = SystemRandom
-
-        strategy = BrokenStrategyWithSettings(storage=BrokenStorage)
-        self.assertTrue(isinstance(strategy.random_string(), str))
-        random.SystemRandom = orig_random