Simplify regex in TestDataFormatterUnordered.py for better readability.

Summary:
Using `(match){3}` instead of `matchmatchmatch`.
This is an update to D10078.

Test Plan: no change in test behavior.

Reviewers: clayborg, sivachandra

Reviewed By: sivachandra

Subscribers: lldb-commits

Differential Revision: http://reviews.llvm.org/D10094

llvm-svn: 238510