Fix syntax

Author: janhohenheim

Diff for: .github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
       run: |
         npm install -g @umbrelladocs/linkspector
         linkspector --version
-        linkspector --files $(git diff --name-only ${{ github.event.before }} ${{ github.sha }} | grep -E '\.md$')
+        linkspector $(git diff --name-only ${{ github.event.before }} ${{ github.sha }} | grep -E '\.md$')
     - name: Install Zola
       run: curl -L ${BASE_URL}/${VERS}/zola-${VERS}-${ARCH}.tar.gz | tar -xz
     - run: ./zola --version