Update asciidoctor to 1.5.6.2

Gemfile

@@ -146,7 +146,7 @@ gem 'rdoc', '~> 4.2'
 gem 'org-ruby', '~> 0.9.12'
 gem 'creole', '~> 0.5.0'
 gem 'wikicloth', '0.8.1'
-gem 'asciidoctor', '~> 1.5.2'
+gem 'asciidoctor', '~> 1.5.6'
 gem 'asciidoctor-plantuml', '0.0.7'
 gem 'rouge', '~> 2.0'
 gem 'truncato', '~> 0.7.9'

Gemfile.lock

@@ -56,7 +56,7 @@ GEM
       faraday_middleware (~> 0.9)
       faraday_middleware-multi_json (~> 0.0)
       oauth2 (~> 1.0)
-    asciidoctor (1.5.3)
+    asciidoctor (1.5.6.2)
     asciidoctor-plantuml (0.0.7)
       asciidoctor (~> 1.5)
     asset_sync (2.2.0)
@@ -998,7 +998,7 @@ DEPENDENCIES
   akismet (~> 2.0)
   allocations (~> 1.0)
   asana (~> 0.6.0)
-  asciidoctor (~> 1.5.2)
+  asciidoctor (~> 1.5.6)
   asciidoctor-plantuml (= 0.0.7)
   asset_sync (~> 2.2.0)
   attr_encrypted (~> 3.0.0)

spec/lib/gitlab/asciidoc_spec.rb

@@ -48,7 +48,7 @@ module Gitlab
           },
           'images' => {
             input: 'image:https://localhost.com/image.png[Alt text" onerror="alert(7)]',
-            output: "<img src=\"https://localhost.com/image.png\" alt=\"Alt text\">"
+            output: "<div>\n<p><span><img src=\"https://localhost.com/image.png\" alt='Alt text\" onerror=\"alert(7)'></span></p>\n</div>"
           },
           'pre' => {
             input: '```mypre"><script>alert(3)</script>',