Remove test marks specific to Python 3.8

Author: khaeru

sdmx/tests/test_testing.py

@@ -1,15 +1,8 @@
 import json
-import sys
-
-import pytest
 
 from sdmx.testing.report import main
 
 
-@pytest.mark.skipif(
-    sys.version_info.minor < 9,
-    reason="Uses dict() | other, not available in Python 3.8",
-)
 def test_report_main(tmp_path):
     # Example input data
     with open(tmp_path.joinpath("TEST.json"), "w") as f: