Async let second review (#1409)
Async let second review (#1409)

* [SE-0317] Flesh out the alternative design for all-explicit suspension points

* [SE-0317] Added discussion of the use of property wrappers instead of `async let` to Alternatives Considered.

* [SE-0317] Added discussion about requiring braces around an `async let` initializer expression to Alternatives Considered.

* [SE-0317] Add a table of contents

* Apply suggestions from code review

Co-authored-by: Kavon Farvardin <d048986756f16e97e1742d05dc046d6cdc4e8051@apple.com>

* [SE-0317] Expand/clarify discussion of requiring "await" of all async lets

* Update 0317-async-let.md

Co-authored-by: Kavon Farvardin <d048986756f16e97e1742d05dc046d6cdc4e8051@apple.com>
Co-authored-by: Ben Cohen <f6358031b01ba395cdd151dcadd901fffc88c517@users.noreply.github.com>
natecook1000/swift-evolution,abertelrud/swift-evolution,abertelrud/swift-evolution,apple/swift-evolution,natecook1000/swift-evolution,apple/swift-evolution