⬆️(package) pin pyparsing from renovate updates

renovate-bot automatically updates pyparsing package version. However,
the package version is pinned as a temporary solution to avoid the app
build failure. It has to be pinned to a version lower than 3.0.

setup.cfg

@@ -28,7 +28,7 @@ install_requires =
     elasticsearch==7.15.2
     ovh==0.5.0
     pydantic==1.8.2
-    pyparsing==3.0.6
+    pyparsing==2.4.7
     python-keystoneclient==4.3.0
     python-swiftclient==3.12.0
     pyyaml==6.0