Bump pygments from 2.4.2 to 2.7.4 in /docker#8

dependabot[bot] wants to merge 1 commit intomainpybokeh/jupyter_notebooks:mainfrom

dependabot/pip/docker/pygments-2.7.4pybokeh/jupyter_notebooks:dependabot/pip/docker/pygments-2.7.4Copy head branch name to clipboard