Bump nokogiri from 1.12.3 to 1.12.4 (#1499)

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

Author: dependabot[bot]

Gemfile.lock

@@ -82,7 +82,7 @@ GEM
       rouge (~> 3.2)
     mini_portile2 (2.6.1)
     minitest (5.14.4)
-    nokogiri (1.12.3)
+    nokogiri (1.12.4)
       mini_portile2 (~> 2.6.1)
       racc (~> 1.4)
     padrino-helpers (0.15.1)