Incorrect relationship label when protocol is not scanned first

[MarcoEidinger]

If subclasses and/or extensions are scanned before their parent class then the class diagram gets generated incorrectly.

Example

class aClass: aProtocol {
    var computedProperty: String { "" }
    func aFunction() {}
}

protocol aProtocol {
    func aProtFunction() {}
}

Current (unexpected) output

Expected output