Bump nokogiri from 1.13.4 to 1.13.6 (ausaccessfed#259)

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.13.4 to 1.13.6.
- [Release notes](https://github.com/sparklemotion/nokogiri/releases)
- [Changelog](https://github.com/sparklemotion/nokogiri/blob/main/CHANGELOG.md)
- [Commits](sparklemotion/nokogiri@v1.13.4...v1.13.6)

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

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

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

Gemfile.lock

@@ -187,9 +187,9 @@ GEM
     mysql2 (0.5.3)
     nenv (0.3.0)
     nio4r (2.5.8)
-    nokogiri (1.13.4-x86_64-darwin)
+    nokogiri (1.13.6-x86_64-darwin)
       racc (~> 1.4)
-    nokogiri (1.13.4-x86_64-linux)
+    nokogiri (1.13.6-x86_64-linux)
       racc (~> 1.4)
     notiffany (0.1.3)
       nenv (~> 0.1)