`{{#each` without key is not a compile time error
`{{#each` without key is not a compile time error

The env should have an opportunity to handle key=null (Ember defaults it
to @index/@identity, for example).

tildeio/glimmer,lbdm44/glimmer-vm,lbdm44/glimmer-vm,tildeio/glimmer,lbdm44/glimmer-vm,glimmerjs/glimmer-vm,glimmerjs/glimmer-vm,tildeio/glimmer,glimmerjs/glimmer-vm