Fix CI doc

Author: frankie567

.github/workflows/documentation.yml

@@ -29,7 +29,7 @@ jobs:
         uses: battila7/get-version-action@v2
       - name: Deploy
         env:
-          DOC_TAG: ${{ steps.version_tag.outputs.version && format('{0}.{1}', steps.version_tag.outputs.major, steps.version_tag.outputs.minor) || 'dev' }}
+          DOC_TAG: ${{ steps.version_tag.outputs.major && steps.version_tag.outputs.minor && format('{0}.{1}', steps.version_tag.outputs.major, steps.version_tag.outputs.minor) || 'dev' }}
         run: |
           git fetch origin gh-pages --depth=1
           mike deploy --push --update-aliases ${{ env.DOC_TAG }} latest