Update permalink structure and downgrade Jekyll version for compatibility

- Changed the permalink structure in the configuration to use 'categories' instead of 'category' for lab URLs.
- Downgraded Jekyll version in the Gemfile from 4.3.0 to 3.10.0 to ensure compatibility with existing plugins and workflows.
- Updated GitHub Actions workflow to use Ruby 3.0 and streamlined the build command for Jekyll.
- Modified lab markdown files to reflect the new 'categories' field for better organization.

.github/workflows/deploy.yml

@@ -24,15 +24,19 @@ jobs:
       - name: Setup Ruby
         uses: ruby/setup-ruby@v1
         with:
-          ruby-version: '3.2'
+          ruby-version: '3.0'
           bundler-cache: true
           
+      - name: Install dependencies
+        run: |
+          bundle install
+          
       - name: Setup Pages
         uses: actions/configure-pages@v4
         
       - name: Build with Jekyll
         run: |
-          bundle exec jekyll build --baseurl "${{ steps.page_url.outputs.base_path }}"
+          bundle exec jekyll build
         env:
           JEKYLL_ENV: production