Set $wgCategoryCollation to 'uca-cs' on cswiki

We'll redo this with support from ops/springle.

This reverts commit 8f90a3629ff6b00b76deef712fb1d9e2974a1472.

Change-Id: Ied90a6f21c7f0bab5b217bec0f282e7934cce5ab