[ci skip] Remove Pratik Naik from Rails core team info.

guides/source/credits.html.erb

@@ -64,7 +64,7 @@ Oscar Del Ben is a software engineer at <a href="http://www.wildfireapp.com/">Wi
 <% end %>
 
 <%= author('Pratik Naik', 'lifo') do %>
-  Pratik Naik is a Ruby on Rails developer at <a href="https://basecamp.com/">Basecamp</a> and also a member of the <a href="http://rubyonrails.org/core">Rails core team</a>. He maintains a blog at <a href="http://m.onkey.org">has_many :bugs, :through =&gt; :rails</a> and has a semi-active <a href="http://twitter.com/lifo">twitter account</a>.
+  Pratik Naik is a Ruby on Rails developer at <a href="https://basecamp.com/">Basecamp</a> and maintains a blog at <a href="http://m.onkey.org">has_many :bugs, :through =&gt; :rails</a>. He also has a semi-active <a href="http://twitter.com/lifo">twitter account</a>.
 <% end %>
 
 <%= author('Emilio Tagua', 'miloops') do %>