Bug 1839 - Change in setuptools breaks stage 2

Need to pin setuptools to < 60 as the newer versions
do not work with stdeb

Fixes Bug 1839

Change-Id: Iba3e9d7d2672e28c3eb410160fb5cb7a6848f7bb
Signed-off-by: beierlm <mark.beierl@canonical.com>