Bump nokogiri from 1.14.2 to 1.15.4

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.14.2 to 1.15.4.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.14.2...v1.15.4)

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

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

Gemfile.lock

@@ -84,12 +84,12 @@ GEM
     nanaimo (0.3.0)
     nap (1.1.0)
     netrc (0.11.0)
-    nokogiri (1.14.2)
-      mini_portile2 (~> 2.8.0)
+    nokogiri (1.15.4)
+      mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     open4 (1.3.4)
     public_suffix (4.0.7)
-    racc (1.6.2)
+    racc (1.7.1)
     redcarpet (3.6.0)
     rexml (3.2.6)
     rouge (2.0.7)