reproducible Alpine: only build webpages every 2h, not twice per hour

                    my_shellext: ".py"

                - 'html_alpine':

                    my_description: 'Build webpages for alpine reproducibility tests'

                    my_timed: '15,45 * * * *'

                    my_timed: '55 H/2 * * *'

                - 'alpine_scheduler':

                    my_description: 'Scheduler for alpine reproducibility tests'

                    my_timed: '0 H/4 * * *'