Update GitHub Actions build file

Author: stedman

.github/workflows/eleventy_build.yml

@@ -16,10 +16,10 @@ jobs:
     # Steps represent a sequence of tasks that will be executed as part of the job
     steps:
     # Checks-out your repository under $GITHUB_WORKSPACE, so your job can access it
-    - uses: actions/checkout@v2
+    - uses: actions/checkout@v3
 
     - name: Setup Node.js environment
-      uses: actions/setup-node@v2
+      uses: actions/setup-node@v3
 
     - name: Install packages
       run: npm ci