Fix buggy auto-correct for 'format' method
Fix buggy auto-correct for 'format' method

Previously the auto-correct for the Style/FormatString Cop modified
the use of 'sprintf' to 'format', which despite being a Ruby Kernel
method, is overridden by this class is too many places to change.
This fixes the incorrect method call and disables the Cop.

alphagov/publisher,alphagov/publisher,alphagov/publisher