dir restructure to support more CGP (#1266)

* rerame res to chain-specs

* split polkadot-parachains dir

* rename dir parachains-common to common

Co-authored-by: joe petrowski <25483142+joepetrowski@users.noreply.github.com>
Co-authored-by: Wilfried Kopp <wilfried@parity.io>
Co-authored-by: Chevdor <chevdor@users.noreply.github.com>

cumulus/.gitlab-ci.yml

@@ -224,7 +224,7 @@ benchmarks:
     - git config remote.origin.fetch "+refs/heads/*:refs/remotes/origin/*"
     # push results to github
     - git checkout -b $BRANCHNAME
-    - git add polkadot-parachains/*
+    - git add parachains/*
     - git commit -m "[benchmarks] pr with weights"
     - git push origin $BRANCHNAME
     # create PR