setup: try a non-pure version of the local Mercurial if the pure fails
Things like `zstd` can make the pure version fails.
FROM debian:%CODENAME%
RUN groupadd -g 1000 build && \
useradd -u 1000 -g 1000 -s /bin/bash -d /build -m build
RUN apt-get update && apt-get install -y \
build-essential \
debhelper \
devscripts \
dh-python \
less \
python \
python-all-dev \
python-docutils \
unzip \
zip