services/nomad/build/buildbot-worker: don't set XBPS_CHROOT_CMD_ARGS='-t'

this was making xbps-uchroot use a tmpfs for the buildroot, which caused
it to hog all the memory for the buildroot's storage

Closes: #217 [via git-merge-pr]

Author: classabbyamp

services/nomad/build/buildbot-worker.nomad

@@ -135,7 +135,6 @@ EOF
           data = <<EOF
 XBPS_MAKEJOBS=${group.value.jobs}
 XBPS_CHROOT_CMD=uchroot
-XBPS_CHROOT_CMD_ARGS='-t'
 XBPS_CCACHE=yes
 XBPS_DEBUG_PKGS=yes
 XBPS_USE_GIT_REVS=yes