BUG: Remove unused itkAffineTransformXX.txt content links.

These interfere with the content link backup script.

Change-Id: Iec8b369d936b7ab4b8be857b04afd699f066c56c
Merge topic 'unused-content-links'

a58465b BUG: Remove unused itkAffineTransformXX.txt content links.