Bump Ruby to 3.3 in Algolia workflow

nokogiri now requires Ruby >= 3.0; the old 2.6 pin causes Bundler to
fail resolving dependencies.

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

Author: nicoalba

.github/workflows/update-algolia.yml

@@ -13,7 +13,7 @@ jobs:
     - uses: actions/checkout@v2
     - uses: ruby/setup-ruby@v1
       with:
-        ruby-version: 2.6 # Not needed with a .ruby-version file
+        ruby-version: '3.3'
         bundler-cache: true # runs 'bundle install' and caches installed gems automatically
     - name: Actually Update Algolia
       env: