CI: only run when changes are made

.github/workflows/release.yml

@@ -18,36 +18,34 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v4
 
-      - name: Check for Docker changes
-        id: docker-changes
+      - name: Check for relevant changes
+        id: changes
         run: |
           CHANGED=0
+          # Fetch the latest changes
           git fetch origin main
-          if [ "$(git rev-list --count HEAD)" -gt 1 ]; then
-            # Ensure that there is more than 1 commit in the history
-            if git diff --name-only HEAD^ HEAD | grep -q "^\.docker/"; then
-              CHANGED=1
-            fi
-          else
-            # If there's no previous commit, assume no changes
-            CHANGED=0
+
+          # Check for changes in .tex, .sty, .cls, or Docker-related files
+          if git diff --name-only HEAD^ HEAD | grep -E "^(.docker/|.*\.(tex|sty|cls)$)" > /dev/null; then
+            CHANGED=1
           fi
+
           echo "changed=${CHANGED}" >> $GITHUB_OUTPUT
 
       - name: Set up Docker
-        if: steps.docker-changes.outputs.changed == '1'
+        if: steps.changes.outputs.changed == '1'
         uses: docker/setup-buildx-action@v3
 
       - name: Login to GitHub Container Registry
-        if: steps.docker-changes.outputs.changed == '1'
+        if: steps.changes.outputs.changed == '1'
         uses: docker/login-action@v3
         with:
           registry: ghcr.io
           username: ${{ github.actor }}
           password: ${{ secrets.GITHUB_TOKEN }}
 
       - name: Build and cache Docker image
-        if: steps.docker-changes.outputs.changed == '1'
+        if: steps.changes.outputs.changed == '1'
         uses: docker/build-push-action@v5
         with:
           context: .docker
@@ -76,7 +74,7 @@ jobs:
         run: echo "sha=$(git rev-parse --short HEAD)" >> $GITHUB_OUTPUT
 
       - name: Create Release
-        if: github.ref == 'refs/heads/main'
+        if: steps.changes.outputs.changed == '1' && github.ref == 'refs/heads/main'
         uses: softprops/action-gh-release@v2
         with:
           draft: false