Bump capybara from 3.19.1 to 3.20.0

Bumps [capybara](https://github.com/teamcapybara/capybara) from 3.19.1 to 3.20.0.
- [Release notes](https://github.com/teamcapybara/capybara/releases)
- [Changelog](https://github.com/teamcapybara/capybara/blob/master/History.md)
- [Commits](https://github.com/teamcapybara/capybara/compare/3.19.1...3.20.0)

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

Gemfile.lock

@@ -96,13 +96,14 @@ GEM
       capistrano (~> 3.7)
       capistrano-bundler
       puma (~> 3.4)
-    capybara (3.19.1)
+    capybara (3.20.0)
       addressable
       mini_mime (>= 0.1.3)
       nokogiri (~> 1.8)
       rack (>= 1.6.0)
       rack-test (>= 0.6.3)
       regexp_parser (~> 1.2)
+      uglifier
       xpath (~> 3.2)
     carrierwave (1.3.1)
       activemodel (>= 4.0.0)