Update Actions to latest version.

Updates to actions to ensure they support node.js 24.  GHA will
default to this version of node.js in June 2026.

This update will fix the following warning message:

```
Node.js 20 actions are deprecated. The following actions are running on Node.js 20 and may not work as expected: actions/cache/restore@v4, fjogeleit/http-request-action@v1. Actions will be forced to run with Node.js 24 by default starting June 2nd, 2026. Please check if updated versions of these actions are available that support Node.js 24. To opt into Node.js 24 now, set the FORCE_JAVASCRIPT_ACTIONS_TO_NODE24=true environment variable on the runner or in your workflow file. Once Node.js 24 becomes the default, you can temporarily opt out by setting ACTIONS_ALLOW_USE_UNSECURE_NODE_VERSION=true. For more information see: https://github.blog/changelog/2025-09-19-deprecation-of-node-20-on-github-actions-runners/
```

Author: stumbo

.github/workflows/gh-pages.yml

@@ -49,6 +49,8 @@ env:
   # Specify the deployment environment:  staging or production
   HUGO_ENVIRONMENT: ${{ vars.HUGO_ENVIRONMENT || 'staging' }}
   HUGO_VERSION: 0.155.3
+  # Temporary to validate Node.js 24 works correctly
+  FORCE_JAVASCRIPT_ACTIONS_TO_NODE24=true
 
 jobs:
   # ----------------------------------------------------------------------------
@@ -65,14 +67,14 @@ jobs:
 
       - name: Get Zotero Version Information
         id: zoteroVersion
-        uses: fjogeleit/http-request-action@v1
+        uses: fjogeleit/http-request-action@v2
         with:
           url: https://api.zotero.org/groups/2914042/items?format=versions
           method: GET
 
       - name: Cache Zotero Bibliography
         id: cache-zotero
-        uses: actions/cache/restore@v4
+        uses: actions/cache/restore@v5.0.3
         with:
           lookup-only: true
           path: |
@@ -87,7 +89,7 @@ jobs:
     if: github.event_name == 'push' || github.event_name == 'pull_request'
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
 
       - name: Check Hugo version consistency
         run: |
@@ -121,14 +123,14 @@ jobs:
     if: always() && (github.event_name == 'push' || github.event_name == 'pull_request' || needs.check.outputs.cacheHit != 'true') && (needs.validate-docs.result == 'success' || needs.validate-docs.result == 'skipped') && (needs.check.result == 'success' || needs.check.result == 'skipped')
     runs-on: ubuntu-latest
     steps:
-      - uses: actions/checkout@v4
+      - uses: actions/checkout@v6
         with:
           submodules: recursive
           fetch-depth: 0
 
       - name: Cache Zotero Bibliography
         id: cache-bib
-        uses: actions/cache@v4
+        uses: actions/cache@v5.0.3
         with:
           path: |
             static/data/bibliography.json
@@ -157,9 +159,9 @@ jobs:
         uses: actions/configure-pages@v5
 
       - name: Setup Node
-        uses: actions/setup-node@v4
+        uses: actions/setup-node@v6
         with:
-          node-version: 18
+          node-version: 24
 
       - run: npm install -g autoprefixer --save-dev  
       - run: npm install -g postcss-cli --save-dev
@@ -172,7 +174,7 @@ jobs:
         run: hugo --cleanDestinationDir -e $HUGO_ENVIRONMENT
 
       - name: Upload artifact
-        uses: actions/upload-pages-artifact@v3
+        uses: actions/upload-pages-artifact@v4
         with:
           path: ./public