Inconsistent "well known symbol" vs "well-known symbol" in Symbol.asyncIterator

[arai-a]

Symbol.asyncIterator's description uses "well known symbol" term with a space between "well" and "known",
but all other Symbol properties use "well-known symbol" term with a hyphen between "well" and "known".

https://tc39.es/ecma262/#sec-symbol.asynciterator

The initial value of Symbol.asyncIterator is the well known symbol @@asyncIterator (Table 1).

https://tc39.es/ecma262/#sec-symbol.hasinstance

The initial value of Symbol.hasInstance is the well-known symbol @@hasInstance (Table 1).

[jmdyck]

In this repo, you don't need to create an Issue just for a subsequent PR to reference.

See #3141 (comment) for more detail.