Confusing part of documentation

[milosa]

The GraphQL const is called CHANGE_POST_TITLE, the method is called upvote() and the text after the code talks about posting a new comment.

These are three different actions. Maybe this should be corrected?

https://github.com/kamilkisiela/apollo-angular/blob/6728bbb7a527d230d45e08878834bf538cdf93db/website/docs/data/mutations.md?plain=1#L158-L202