Add dependency installation to vale rule

(cherry picked from commit 989f378)

Author: rustagir

.github/workflows/vale-tdbx.yml

@@ -12,6 +12,9 @@ jobs:
       - name: checkout
         uses: actions/checkout@master
 
+      - name: Install docutils
+        run: sudo apt-get install -y docutils
+
       - id: files
         uses: masesgroup/retrieve-changed-files@v2
         with: