Github: retrieve individual files from Github in a Dockerfile

FROM alpine:edge

ARG githubtoken=1852...

RUN apk add --no-cache curl wget

RUN curl -o /var/mbqt/lib/MBQT/Bootstrap.pm -H "Authorization: token $githubtoken" -H 'Accept: application/vnd.github.v3.raw' -L https://api.github.com/repos///contents/perl/lib/MBQT/Bootstrap.pm