Use posix_spawn on macOS 12#47

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tov wants to merge 8 commits intojanestreet:masterfrom

tov:posix_spawn

Commits on Jul 26, 2022

CI: Specify macOS versions.

tov
authored and
jtov-js
committed
Use posix_spawn instead of vfork on mac OS >= 12.

tov
authored and
jtov-js
committed