Add wildcard's ability to match nothing

[TysonMN]

I don't think the section about the wildcard pattern preciously describes the current and desired behavior. Specifically, in addition to being able to match anything, the wildcard pattern can also match nothing at all as described in dotnet/fsharp#1592. As I understand it, this feature is not mentioned in the documentation.

Can a description of this feature be added to the documentation?

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Document Details

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• ID: 8a3ed054-03c9-375f-403b-68f0356d5870
• Version Independent ID: 3c167003-13e8-359b-e919-693258e7f48b
• Content: Pattern Matching - F#
• Content Source: docs/fsharp/language-reference/pattern-matching.md
• Product: dotnet-fsharp
• GitHub Login: @cartermp
• Microsoft Alias: phcart

[abelbraaksma]

This behaviour has now slightly changed, see: dotnet/fsharp#14055. @edgarfgp, do we need to update the docs by mentioning the new warning?

[edgarfgp]

@abelbraaksma i think we should . Not sure the timing to do it ?. @vzarytovskii any guidance on when we should do it ?