Bump nokogiri in /docs in the bundler group across 1 directory

Bumps the bundler group with 1 update in the /docs directory: [nokogiri](https://github.com/sparklemotion/nokogiri).


Updates `nokogiri` from 1.18.4 to 1.18.8
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](https://github.com/sparklemotion/nokogiri/compare/v1.18.4...v1.18.8)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-version: 1.18.8
  dependency-type: indirect
  dependency-group: bundler
...

Signed-off-by: dependabot[bot] <support@github.com>

docs/Gemfile.lock

@@ -205,15 +205,14 @@ GEM
       rb-fsevent (~> 0.10, >= 0.10.3)
       rb-inotify (~> 0.9, >= 0.9.10)
     mercenary (0.3.6)
-    mini_portile2 (2.8.8)
     minima (2.5.1)
       jekyll (>= 3.5, < 5.0)
       jekyll-feed (~> 0.9)
       jekyll-seo-tag (~> 2.1)
     minitest (5.19.0)
-    nokogiri (1.18.4-aarch64-linux-gnu)
+    nokogiri (1.18.8-aarch64-linux-gnu)
       racc (~> 1.4)
-    nokogiri (1.18.4-x86_64-linux-gnu)
+    nokogiri (1.18.8-x86_64-linux-gnu)
       racc (~> 1.4)
     octokit (4.25.1)
       faraday (>= 1, < 3)