Use fern-api/setup-fern-cli@v1 action to install Fern CLI (#65)

Co-authored-by: Niels Swimberghe <3382717+Swimburger@users.noreply.github.com>
Co-authored-by: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: 3 people

.github/workflows/fern.yml

@@ -11,13 +11,13 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v2
-      - name: Install fern
-        run: npm install -g fern-api
+      - name: Setup Fern CLI
+        uses: fern-api/setup-fern-cli@v1
       - name: fern check
         run: fern check
       - name: Verify generated code is up to date
         run: |
           fern generate
           git --no-pager diff --exit-code
         env:
-          FERN_TOKEN: dummy
+          FERN_TOKEN: dummy