chore(python): remove configure_previous_major_version_branches#143

tswast merged 2 commits intomaingoogleapis/python-bigquery-magics:mainfrom

owl-bot-update-lock-fbbc8db67afd8b7d71bf694c5081a32da0c528eba166fbcffb3b6e56ddf907d5googleapis/python-bigquery-magics:owl-bot-update-lock-fbbc8db67afd8b7d71bf694c5081a32da0c528eba166fbcffb3b6e56ddf907d5Copy head branch name to clipboard