Bump uglifier from 4.1.6 to 4.1.7 (#58)

Bumps [uglifier](https://github.com/lautis/uglifier) from 4.1.6 to 4.1.7.
- [Changelog](https://github.com/lautis/uglifier/blob/master/CHANGELOG.md)
- [Commits](lautis/uglifier@v4.1.6...v4.1.7)

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

Gemfile.lock

@@ -209,7 +209,7 @@ GEM
     turbolinks-source (5.1.0)
     tzinfo (1.2.5)
       thread_safe (~> 0.1)
-    uglifier (4.1.6)
+    uglifier (4.1.7)
       execjs (>= 0.3.0, < 3)
     unicode-display_width (1.3.0)
     web-console (3.5.1)