Use setup-fern-cli GitHub Action in preview-docs workflow (#98)

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/check.yml

@@ -13,8 +13,8 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Install Fern CLI tool
-        run: npm install -g fern-api
+      - name: Setup Fern CLI
+        uses: fern-api/setup-fern-cli@v1
 
       - name: Check API is valid
         run: fern check

.github/workflows/preview-docs.yml

@@ -12,8 +12,8 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Install Fern CLI tool
-        run: npm install -g fern-api
+      - name: Setup Fern CLI
+        uses: fern-api/setup-fern-cli@v1
 
       - name: Generate preview URL
         id: generate-docs

.github/workflows/publish-docs.yml

@@ -13,8 +13,8 @@ jobs:
       - name: Checkout repository
         uses: actions/checkout@v4
 
-      - name: Install Fern CLI tool
-        run: npm install -g fern-api
+      - name: Setup Fern CLI
+        uses: fern-api/setup-fern-cli@v1
 
       - name: Publish Docs
         env: