Update dependency packaging to v21.2

Author: renovate-bot

docs/requirements.txt

@@ -28,7 +28,7 @@ MarkupSafe==2.0.1
 mccabe==0.6.1
 mypy-extensions==0.4.3
 nodeenv==1.6.0
-packaging==21.0
+packaging==21.2
 pathspec==0.9.0
 pbr==5.6.0
 platformdirs==2.3.0