Bump nokogiri from 1.13.9 to 1.15.5

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.13.9 to 1.15.5.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.13.9...v1.15.5)

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

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

Gemfile.lock

@@ -147,7 +147,7 @@ GEM
     multipart-post (2.2.3)
     mysql2 (0.4.10)
     nio4r (2.5.8)
-    nokogiri (1.13.9-x86_64-linux)
+    nokogiri (1.15.5-x86_64-linux)
       racc (~> 1.4)
     oauth2 (1.4.11)
       faraday (>= 0.17.3, < 3.0)
@@ -168,7 +168,7 @@ GEM
     puma (6.0.0)
       nio4r (~> 2.0)
     raabro (1.4.0)
-    racc (1.6.0)
+    racc (1.7.3)
     rack (2.2.4)
     rack-cors (1.1.1)
       rack (>= 2.0.0)