Use bundle.mainreporoot as "hg root"
Review Request #11146 — Created Aug. 20, 2020 and submitted — Latest diff uploaded
This saves one more hg binary call and replaces "hg root" with the value of "bundle.mainreporoot" of "hg showconfig" as it is the same.
Checked the debug outpot of
rbt postthat
it do not callhg rootand uses the correct path.