ci: validate template before pushing (#11867)

.github/workflows/dogfood.yaml

@@ -58,26 +58,38 @@ jobs:
 
   deploy_template:
     needs: build_image
-    if: github.ref == 'refs/heads/main'
     runs-on: ubuntu-latest
     steps:
       - name: Checkout
         uses: actions/checkout@v4
 
+      - name: Setup Terraform
+        uses: ./.github/actions/setup-tf
+
+      - name: Terraform init and validate
+        run: |
+          cd dogfood
+          terraform init -upgrade
+          terraform validate
+
       - name: Get short commit SHA
+        if: github.ref == 'refs/heads/main'
         id: vars
         run: echo "sha_short=$(git rev-parse --short HEAD)" >> $GITHUB_OUTPUT
 
       - name: Get latest commit title
+        if: github.ref == 'refs/heads/main'
         id: message
         run: echo "pr_title=$(git log --format=%s -n 1 ${{ github.sha }})" >> $GITHUB_OUTPUT
 
       - name: "Get latest Coder binary from the server"
+        if: github.ref == 'refs/heads/main'
         run: |
           curl -fsSL "https://dev.coder.com/bin/coder-linux-amd64" -o "./coder"
           chmod +x "./coder"
 
       - name: "Push template"
+        if: github.ref == 'refs/heads/main'
         run: |
           ./coder templates push $CODER_TEMPLATE_NAME --directory $CODER_TEMPLATE_DIR --yes --name=$CODER_TEMPLATE_VERSION --message="$CODER_TEMPLATE_MESSAGE" --variable jfrog_url=${{ secrets.JFROG_URL }}
         env: