Bump nokogiri from 1.13.2 to 1.13.4 (JabRef#6016)

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.13.2 to 1.13.4.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/v1.13.4/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.13.2...v1.13.4)

---
updated-dependencies:
- dependency-name: nokogiri
  dependency-type: direct:production
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Gemfile.lock

@@ -65,10 +65,10 @@ GEM
     mini_portile2 (2.8.0)
     multipart-post (2.1.1)
     namae (1.1.1)
-    nokogiri (1.13.2)
+    nokogiri (1.13.4)
       mini_portile2 (~> 2.8.0)
       racc (~> 1.4)
-    nokogiri (1.13.2-x64-mingw32)
+    nokogiri (1.13.4-x64-mingw32)
       racc (~> 1.4)
     octokit (4.21.0)
       faraday (>= 0.9)