Set both Symbol.species and "@@species" on Concast constructor (#7403)
Set both Symbol.species and "@@species" on Concast constructor (#7403)

An attempt to address the problems I speculated about in
https://github.com/apollographql/apollo-client/issues/6520#issuecomment-736899757

Theory: in the Hermes JS engine, Symbol.species is not defined, so
Object.defineProperty was not called, but perhaps "@@species" was getting
set somewhere else by a polyfill library, causing the zen-observable
library to fall back to "@@species" instead of using/ignoring the
nonexistent Symbol.species symbol.

apollographql/apollo-client,apollographql/apollo-client