Typo fix

[skip ci] Fixing the typo which is formed a not required link.  Check here http://api.rubyonrails.org/classes/ActionController/Base.html  under paramters section
keeping it under tt tag

actionpack/lib/action_controller/base.rb

@@ -59,7 +59,7 @@ module ActionController
   #   <input type="text" name="post[address]" value="hyacintvej">
   #
   # A request stemming from a form holding these inputs will include <tt>{ "post" => { "name" => "david", "address" => "hyacintvej" } }</tt>.
-  # If the address input had been named "post[address][street]", the params would have included
+  # If the address input had been named <tt>post[address][street]</tt>, the params would have included
   # <tt>{ "post" => { "address" => { "street" => "hyacintvej" } } }</tt>. There's no limit to the depth of the nesting.
   #
   # == Sessions