Fix rust warning

[Montel]

warning: unused import: WorkspaceEdit --> tools/lsp/language.rs:45:85 | 45 | ServerInfo, TextDocumentSyncCapability, TextEdit, Url, WorkDoneProgressOptions, WorkspaceEdit, | ^^^^^^^^^^^^^ | = note: #[warn(unused_imports)] on by default

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[ogoffart]

Looks like the warning maybe depends on some features or some platform because that doesn't compile. Maybe we need to add the use in a smaller scope

[hunger]

#4629 fixes this as a drive-by. I plan to merge that really-soon-now(TM).

[hunger]

This was fixed in #4629.