Update pygithub from 1.51 to 1.52 (#1607)
Update pygithub from 1.51 to 1.52 (#1607)

Co-authored-by: Fábio Rosado <504d498c4e6912c88badf931727242f17b94f32f@gmail.com>
FabioRosado/opsdroid,opsdroid/opsdroid,jacobtomlinson/opsdroid