Remove corrupted Gemfile.lock and fix GitHub Actions workflow

Author: tomvannuenen

.github/workflows/jekyll.yml

@@ -25,10 +25,10 @@ jobs:
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: '3.1'
-          bundler-cache: true
-          cache-version: 0
-        env:
-          BUNDLE_DEPLOYMENT: false
+          bundler-cache: false
+      
+      - name: Install dependencies
+        run: bundle install
 
       - name: Setup Pages
         id: pages