Bump nokogiri from 1.15.7 to 1.19.1 in /docs

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.15.7 to 1.19.1.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.15.7...v1.19.1)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-version: 1.19.1
  dependency-type: indirect
...

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

Author: dependabot[bot]

docs/Gemfile.lock

@@ -211,18 +211,14 @@ GEM
       rb-inotify (~> 0.9, >= 0.9.10)
     logger (1.6.6)
     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 (5.25.5)
-    nokogiri (1.15.7)
-      mini_portile2 (~> 2.8.2)
+    nokogiri (1.19.1-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.15.7-x86_64-darwin)
-      racc (~> 1.4)
-    nokogiri (1.15.7-x86_64-linux)
+    nokogiri (1.19.1-x86_64-linux-gnu)
       racc (~> 1.4)
     octokit (4.25.1)
       faraday (>= 1, < 3)