Land rapid7#5166, update redcarpet for XSS vuln

Author: Brent Cook

Gemfile.lock

@@ -177,7 +177,7 @@ GEM
       json (~> 1.4)
     recog (1.0.27)
       nokogiri
-    redcarpet (3.1.2)
+    redcarpet (3.2.3)
     rkelly-remix (0.0.6)
     robots (0.10.1)
     rspec (2.99.0)