fix loofah to 2.3.1 and upgrade rails-html-sanitizer

Gemfile

@@ -24,6 +24,7 @@ gem 'oauth-plugin',            git: 'https://github.com/CartoDB/oauth-plugin.git
 gem 'hiredis',                 '~> 0.6.1'
 gem 'redis',                   '~> 3.3.5'
 
+gem 'loofah',                  '~> 2.3.1'
 gem 'nokogiri',                '~> 1.10'
 gem 'statsd-client',           '0.0.7', require: 'statsd'
 gem 'aws-sdk-s3',              '~> 1'

Gemfile.lock

@@ -119,7 +119,7 @@ GEM
     compass-import-once (1.0.5)
       sass (>= 3.2, < 3.5)
     concurrent-ruby (1.1.4)
-    crass (1.0.4)
+    crass (1.0.6)
     daemons (1.2.4)
     db-query-matchers (0.4.0)
     dbf (2.0.6)
@@ -233,7 +233,7 @@ GEM
     json-schema (2.1.9)
     jwt (2.2.1)
     kgio (2.10.0)
-    loofah (2.4.0)
+    loofah (2.3.1)
       crass (~> 1.0.2)
       nokogiri (>= 1.5.9)
     mail (2.7.1)
@@ -306,8 +306,8 @@ GEM
       activesupport (>= 4.2.0, < 5.0)
       nokogiri (~> 1.6)
       rails-deprecated_sanitizer (>= 1.0.1)
-    rails-html-sanitizer (1.0.4)
-      loofah (~> 2.4, >= 2.4.0)
+    rails-html-sanitizer (1.3.0)
+      loofah (~> 2.3)
     rails_warden (0.5.8)
       warden (>= 1.0.0)
     railties (4.2.11)
@@ -498,6 +498,7 @@ DEPENDENCIES
   hiredis (~> 0.6.1)
   instagram-continued-continued
   json-schema (= 2.1.9)
+  loofah (~> 2.3.1)
   memory_profiler
   mime-types (= 3.1)
   mocha (= 1.1.0)