Fix typo in List Subcollections of a Document (#10)
Fix typo in List Subcollections of a Document (#10)

On line 567, the argument 'colleciton' is passed as an argument into the forEach function.
The argument should be 'collection', just a small typo.

I've went ahead and fixed this typo.
firebase/snippets-node,firebase/snippets-node,firebase/snippets-node