cubicweb-vcsfile #2924045 hgrc-path option is unreliable [validation pending]

it sets HGRCPATH in the looping task, which may be too late if an access to mercurial happens somewhere else.

prioritynormal
typebug
done in1.13.2
load0.250
load left0.000
closed by#dd8e7c4af779 hooks: set HGRCPATH on startup (closes #2924045)
patchhooks: set HGRCPATH on startup [applied]