fix: field selection set final values

[MarkoMin]

AFAIK scalar and enum values are considered to be distinct throughout the specification so I think this would be more correct description of field selection.

I didn't change the sentence below the modified one because it doesn't contain any enum values, but I may add some if that'd be beneficial.

It really is a nitpick, but I stopped on it while reading the spec.

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• ✅ login: MarkoMin / name: mmin (0ecb37c, 2e728a4, e44d837, f9c82f6)

[benjie]

We have the concept of "leaf fields" and "leaf values" already (though it is introduced later in the spec), maybe we should reference that here instead. One concern at the moment is the current wording doesn't handle lists of scalars/enums (or lists of those lists!).

It's still better than what we currently have though; thanks for the contribution!

[martinbonnin]

I've pre-emptively added this to the April wg: graphql/graphql-wg#1947
@MarkoMin feel free to add yourself to the agenda

[MarkoMin]

Sorry, I forgot formatting. Now tests should pass.

[martinbonnin]

Thanks! For the record, I'm not sure this requires a working group item, I'm fine to merge this async. I mostly added it as a forcing function to review this PR if we haven't acted by then.