A quick `bundle update` appears to be just the ticket:<p><pre><code>    …
    Installing rails-html-sanitizer 1.0.3 (was 1.0.2)
    Installing actionmailer 4.2.5.1 (was 4.2.5)
    Installing activemodel 4.2.5.1 (was 4.2.5)
    Installing activerecord 4.2.5.1 (was 4.2.5)
    Installing railties 4.2.5.1 (was 4.2.5)
    Installing rails 4.2.5.1 (was 4.2.5)
    …
    Bundle updated!</code></pre>