Prevent vanished players from being in plot kick autocompletion

[PapiCapi]

Overview

Fixes #4484

Description

I added the parameter PlotPlayer<?> issuer to the method TabCompletions#completePlayersInPlot to be able to call the PlotPlayer#canSee method. Moreover, it makes sense to me that a player should be supplied to this method to have its "personalized" completions.
I didn't add null check in my if block as the parameter is already annotated with @NonNull.

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[SirYwell]

Looks good, thanks.

[PierreSchwang]

Not sure if this is expected to be public API and should rather be deprecated instead of changing the signature without keeping compatibility?

[PapiCapi]

If you want, i can create another method with the same signature as the initial one but i don't really understand why TabCompletions should be part of the API

[PierreSchwang]

If you want, i can create another method with the same signature as the initial one but i don't really understand why TabCompletions should be part of the API

It's a static method available for use by addons, which might register Commands themselves and use the Tab-Completion logic. In the end, it's most likely a very small chance - so both is fine for me ig