Log Message:
py-mercurial: update to 6.7.2.

Mercurial 6.7.2

Exceptional release following a large performance regression when
cloning.

We are setting up automated benchmarks to reduce the likelihood of
regressions of the sort from happening in the future.

    phases: avoid a potentially costly dictionary interation in some case
    phases: update the phase set as we go during retract boundary
    bundle2: make the "hgtagsfnodes" part advisory

Mercurial 6.7.1

Exceptional release following a crash found in delta code that can
be triggered with complex repository shapes.

    delta-search: fix crash caused by unbound variable
    sshpeer: fix path when handling invalid url exception
    subrepo: fix normalizing paths with scheme