dirstate-v2: fix infinite loop in pure packer Due to the naive approach to path relative-ness, some tree shapes like the one introduced in the associated test could result in the packer going into an endless loop which allocated new `Node` objects endlessly until the process was killed by Linux's OOM killer. Differential Revision: https://phab.mercurial-scm.org/D12170

cat >> $HGRCPATH <<EOF
[extensions]
narrow=
[experimental]
changegroup3 = True
EOF