ci: fix iast_memcheck flakyness [backport 2.9] (#10154)

Backport 8490a40 from #10153 to 2.9.

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Co-authored-by: Federico Mon <[email protected]>

tests/appsec/iast_memcheck/test_iast_mem_check.py

@@ -102,7 +102,9 @@ def test_propagation_memory_check(origin1, origin2, iast_span_defaults):
             _initializer_size = initializer_size()
             assert _initializer_size > 0
 
-        assert _num_objects_tainted == num_objects_tainted()
+        # Some tainted pyobject is freed, and Python may reuse the memory address
+        # hence the number of tainted objects may be the same or less
+        assert _num_objects_tainted in (num_objects_tainted(), num_objects_tainted() - 1)
         assert _active_map_addreses_size == active_map_addreses_size()
         assert _initializer_size == initializer_size()
         reset_context()