Bump loofah from 2.2.2 to 2.3.1

Bumps [loofah](https://github.com/flavorjones/loofah) from 2.2.2 to 2.3.1.
- [Release notes](https://github.com/flavorjones/loofah/releases)
- [Changelog](https://github.com/flavorjones/loofah/blob/master/CHANGELOG.md)
- [Commits](https://github.com/flavorjones/loofah/compare/v2.2.2...v2.3.1)

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

Gemfile.lock

@@ -48,7 +48,7 @@ GEM
     builder (3.2.3)
     byebug (10.0.2)
     concurrent-ruby (1.0.5)
-    crass (1.0.4)
+    crass (1.0.5)
     erubi (1.7.1)
     ffi (1.9.25)
     globalid (0.4.1)
@@ -59,7 +59,7 @@ GEM
       rb-fsevent (~> 0.9, >= 0.9.4)
       rb-inotify (~> 0.9, >= 0.9.7)
       ruby_dep (~> 1.2)
-    loofah (2.2.2)
+    loofah (2.3.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.0)
@@ -69,12 +69,12 @@ GEM
     method_source (0.9.0)
     mimemagic (0.3.2)
     mini_mime (1.0.1)
-    mini_portile2 (2.3.0)
+    mini_portile2 (2.4.0)
     minitest (5.11.3)
     msgpack (1.2.4)
     nio4r (2.3.1)
-    nokogiri (1.8.5)
-      mini_portile2 (~> 2.3.0)
+    nokogiri (1.10.5)
+      mini_portile2 (~> 2.4.0)
     pg (1.1.3)
     puma (3.12.0)
     rack (2.0.5)