Bump nokogiri from 1.18.5 to 1.18.6

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.18.5 to 1.18.6.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.18.5...v1.18.6)

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

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

Author: dependabot[bot]

Gemfile.lock

@@ -68,7 +68,7 @@ GEM
     net-smtp (0.5.1)
       net-protocol
     nkf (0.2.0)
-    nokogiri (1.18.5)
+    nokogiri (1.18.6)
       mini_portile2 (~> 2.8.2)
       racc (~> 1.4)
     ostruct (0.6.1)