Update contributing guidelines and the script that checks that reno notes are updated for each PR

.github/renos_updated.sh

@@ -11,7 +11,8 @@ if [ -z $CHANGED_SOURCE_FILES ]; then
     exit 0;
 fi;
 
-CHANGED_RELEASE_NOTES=$(git diff --name-only origin/main $GITHUB_SHA -- releasenotes)
+CHANGED_RELEASE_NOTES=$(git diff --name-only origin/main $GITHUB_SHA -- spec_releasenotes)
+CHANGED_RELEASE_NOTES+=$(git diff --name-only origin/main $GITHUB_SHA -- ast_releasenotes)
 for file in $CHANGED_RELEASE_NOTES
 do
    root=$(echo "./$file" | cut -d / -f 3 )
@@ -21,5 +22,5 @@ do
    fi
 done
 
-echo Please add or update a release note in ./releasenotes >&2
+echo Please add or update a release note in ./spec_releasenotes or ./ ast_releasenotes >&2
 exit 1

CONTRIBUTING.md

@@ -144,6 +144,10 @@ documentation at the same time as the code. To accomplish this we use the
 [reno](https://docs.openstack.org/reno/latest/) tool which enables a Git-based
 workflow for writing and compiling release notes.
 
+Release notes are separated for updates to the specification and the
+grammar/ast generator. The specification release notes are in `spec_releasenotes`
+and the ast/grammar release notes are in `ast_releasenotes`.
+
 #### Adding a new release note
 
 Making a new release note is quite straightforward. Ensure that you have reno
@@ -152,7 +156,7 @@ installed with::
     pip install -U reno
 
 Once you have reno installed you can make a new release note by running in
-your local repository checkout's root::
+your local repository checkout's spec or ast releasenotes dir::
 
     reno new short-description-string