Mongoose 7.0.0发布

BREAKING CHANGE: copy schema options when merging schemas using new Schema() or Schema.prototype.add() #13092
feat(types): export mongodb types more robustly #12948 simon-abbott
docs: fix populate docs #13090 hasezoey
docs(migrating_to_6): added info about removal of reconnectTries and reconnectInterval options #13083 lpizzinidev