Install asciidoctor in CI (#6)

.devcontainer/devcontainer.json

@@ -4,7 +4,8 @@
     "vscode": {
       "extensions": [
         "asciidoctor.asciidoctor-vscode",
-        "ms-vscode.makefile-tools"
+        "ms-vscode.makefile-tools",
+        "chrischinchilla.vale-vscode"
       ]
     }
   }

.github/workflows/continuous_integration.yaml

@@ -17,6 +17,8 @@ jobs:
   lint:
     runs-on: ubuntu-latest
     steps:
+      - name: Install Asciidoctor
+        run: sudo apt-get install -y asciidoctor
       - name: Checkout
         uses: actions/checkout@v4
       - name: Vale