Fixed a profdata file size detection on Windows system.

The space symbols are allowed in the group names on Windows system (as
example: Domain Users). In that case the test extracts a wrong field
from the output to get a size of the profdata file.

This patch avoids a printing of the group names in the test output and
extracts a proper field as a file size.

Differential Revision: https://reviews.llvm.org/D69317