Sort @deprecated completions lower than others

[DanielRosenwasser]

If we do #43710, the first thing you'll see every time you request completions on a string is a bunch of crossed-out properties. Ideally, we never would've shown these properties anyway, but we traditionally had to have them there because ES6.

Originally posted by @DanielRosenwasser in #43710 (comment)

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@deprecated has its own NodeFlags entry right now, so you just have to use the rules from the checker to decide if the signature as a whole should be considered deprecated (basically, whether all the signature's declarations are deprecated). I don't know the sort order code but I assume it would be easy.

Originally posted by @sandersn in #43710 (comment)