Fix skipping of some elements in makrdown

lib/gitlab/markdown.rb

@@ -115,15 +115,17 @@ module Gitlab
         suffix     = $~[:suffix]
         type       = TYPES.select{|t| !$~[t].nil?}.first
-        next unless type
-
-        identifier = $~[type]
-
-        # Avoid HTML entities
-        if prefix && suffix && prefix[0] == '&' && suffix[-1] == ';'
-          match
-        elsif ref_link = reference_link(type, identifier)
-          "#{prefix}#{ref_link}#{suffix}"
+        if type
+          identifier = $~[type]
+
+          # Avoid HTML entities
+          if prefix && suffix && prefix[0] == '&' && suffix[-1] == ';'
+            match
+          elsif ref_link = reference_link(type, identifier)
+            "#{prefix}#{ref_link}#{suffix}"
+          else
+            match
+          end
         else
           match
         end