Bump sprockets-rails from 3.4.1 to 3.4.2

Bumps [sprockets-rails](https://github.com/rails/sprockets-rails) from 3.4.1 to 3.4.2.
- [Release notes](https://github.com/rails/sprockets-rails/releases)
- [Commits](https://github.com/rails/sprockets-rails/compare/v3.4.1...v3.4.2)

---
updated-dependencies:
- dependency-name: sprockets-rails
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Gemfile.lock

@@ -87,7 +87,7 @@ GEM
       reline (>= 0.2.7)
     jbuilder (2.11.3)
       activesupport (>= 5.0.0)
-    loofah (2.12.0)
+    loofah (2.13.0)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.1)
@@ -189,7 +189,7 @@ GEM
     sprockets (4.0.2)
       concurrent-ruby (~> 1.0)
       rack (> 1, < 3)
-    sprockets-rails (3.4.1)
+    sprockets-rails (3.4.2)
       actionpack (>= 5.2)
       activesupport (>= 5.2)
       sprockets (>= 3.0.0)