Specify DOCS_VERSION in the env

Author: vrom911

.github/workflows/publish-docs.yaml

@@ -36,6 +36,8 @@ jobs:
         authToken: '${{ secrets.CACHIX_CARDANO_SCALING_AUTH_TOKEN }}'
 
     - name: Build stable (i.e. from `release`) documentation
+      env:
+        DOCS_VERSION: ${{ steps.get_version.outputs.version }}
       working-directory: docs
       run: |
         echo "Building documentation for stable version: $DOCS_VERSION"
@@ -59,6 +61,8 @@ jobs:
         sed -i 's|head-protocol|head-protocol/unstable|' docusaurus.config.js
 
     - name: Build /unstable documentation
+      env:
+        DOCS_VERSION: unstable
       working-directory: docs
       run: |
         echo "Building documentation for unstable version"