Bump nokogiri from 1.15.2 to 1.15.4

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.15.2 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@v1.15.2...v1.15.4)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <[email protected]>

Gemfile.lock

@@ -28,12 +28,12 @@ GEM
       rb-inotify (~> 0.9, >= 0.9.10)
     lumberjack (1.2.8)
     method_source (0.9.2)
-    mini_portile2 (2.8.2)
+    mini_portile2 (2.8.4)
     mustermann (2.0.2)
       ruby2_keywords (~> 0.0.1)
     nenv (0.3.0)
     nio4r (2.5.9)
-    nokogiri (1.15.2)
+    nokogiri (1.15.4)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     notiffany (0.1.3)
@@ -44,7 +44,7 @@ GEM
       method_source (~> 0.9.0)
     puma (6.2.2)
       nio4r (~> 2.0)
-    racc (1.6.2)
+    racc (1.7.1)
     rack (2.2.6.4)
     rack-protection (2.2.4)
       rack