Remove redundant mercurial config from run-task docker image setup (#884)

web.cacerts is already set by the mercurial debian package.

Author: jcristau

taskcluster/docker/run-task/system-setup.sh

@@ -19,14 +19,6 @@ apt-get install -y --force-yes --no-install-recommends \
     mercurial \
     git
 
-# mercurial setup
-CERT_PATH=/etc/ssl/certs/ca-certificates.crt
-cat >/etc/mercurial/hgrc.d/cacerts.rc <<EOF
-[web]
-cacerts = ${CERT_PATH}
-EOF
-chmod 644 /etc/mercurial/hgrc.d/cacerts.rc
-
 apt-get clean
 apt-get autoclean
 rm -rf /var/lib/apt/lists/