How do I cast an Any value with nil in it to a Any?

I am using reflection to try to check if a struct has a nil value.

struct MyStruct {
    let myString: String?
}

let properties = Mirror(reflecting: MyStruct(myString: nil)).children.filter { $0.label != nil }

for property in properties {
    if property.value == nil { // value has type "Any" will always fail.
        print("property \(property.label!) is nil")
    }
}

How do I cast the Any type to Any?