Bump nokogiri from 1.10.4 to 1.13.4

Bumps [nokogiri](https://github.com/sparklemotion/nokogiri) from 1.10.4 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@v1.10.4...v1.13.4)

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

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

Gemfile.lock

@@ -70,10 +70,11 @@ GEM
     mail (2.7.1)
       mini_mime (>= 0.1.1)
     mini_mime (1.0.2)
-    mini_portile2 (2.4.0)
+    mini_portile2 (2.8.0)
     minitest (5.11.3)
-    nokogiri (1.10.4)
-      mini_portile2 (~> 2.4.0)
+    nokogiri (1.13.4)
+      mini_portile2 (~> 2.8.0)
+      racc (~> 1.4)
     parallel (1.17.0)
     parser (2.6.3.0)
       ast (~> 2.4.0)
@@ -85,6 +86,7 @@ GEM
       actionmailer (>= 3)
       premailer (~> 1.7, >= 1.7.9)
     public_suffix (3.1.1)
+    racc (1.6.0)
     rack (1.6.11)
     rack-test (0.6.3)
       rack (>= 1.0)