[Demangle] Implement missing `Node::Kind::OutlinedInitializeWithTakeN…

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…oValueWitness`

Implements de/remangler support for WOB manglings.

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@swift-ci please build toolchain macOS platform

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@eeckstein I couldn't come up with a reduction for this based on swift-testing failure in swiftlang/swift-testing#1136

It should be something like this:

public protocol P {
}

public protocol Q : P {
}

public protocol W : P {
}

public enum Node : W {
    case test(a: String, b: String)
}

public func repro(node: Node) {
    if let x = node as? any Q { print(x) }
}

But that generates WOb whatever I do...

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@swift-ci please build toolchain macOS platform

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@swift-ci please build toolchain macOS platform

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@swift-ci please test