Bump oj from 3.8.1 to 3.9.0 (#11611)

Bumps [oj](https://github.com/ohler55/oj) from 3.8.1 to 3.9.0.
- [Release notes](https://github.com/ohler55/oj/releases)
- [Changelog](https://github.com/ohler55/oj/blob/develop/CHANGELOG.md)
- [Commits](https://github.com/ohler55/oj/compare/v3.8.1...v3.9.0)

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

Gemfile.lock

@@ -385,7 +385,7 @@ GEM
       concurrent-ruby (~> 1.0, >= 1.0.2)
       sidekiq (>= 3.5)
       statsd-ruby (~> 1.4, >= 1.4.0)
-    oj (3.8.1)
+    oj (3.9.0)
     omniauth (1.9.0)
       hashie (>= 3.4.6, < 3.7.0)
       rack (>= 1.6.2, < 3)
@@ -728,7 +728,7 @@ DEPENDENCIES
   nilsimsa!
   nokogiri (~> 1.10)
   nsa (~> 0.2)
-  oj (~> 3.8)
+  oj (~> 3.9)
   omniauth (~> 1.9)
   omniauth-cas (~> 1.1)
   omniauth-saml (~> 1.10)