Fix "nullable to primitive type" snippets in nullable-value-types.md

[MangelMaxime]

Summary

Hello,

when reading the documentation for F# nullable I found the second snippet equivalent to the one above.

This seems suspicious to me, so I am mostly opening this PR to trigger a discussion with the F# team to check if this is expected or not.

After experimenting with the code, I think the intended snippet is something like proposed in this PR:

open System
open FSharp.Linq

let nullableFloat = Nullable 10.0
let standardFloat = float nullableFloat

printfn $"value is %f{float standardFloat}"

Can someone from the F# team confirm or invalidate my suspicions?

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Internal previews

📄 File	🔗 Preview link
docs/fsharp/language-reference/nullable-value-types.md	docs/fsharp/language-reference/nullable-value-types

[T-Gro]

You are correct @MangelMaxime , this has been a copy-paste mistake in the docs most likely.
The second example should indeed use an operator like float to convert.

[BillWagner]

Thanks @MangelMaxime

This LGTM, and I'll now.