Problematic default value returned as the DeviceId

[kenkendk]

Try using the library with no sources supplied:

Console.WriteLine(new DeviceIdBuilder().ToString());

This returns the string WERC8GMRZGE196QVYK49JVXS4GKTWGF4CJDS6K54JPCHPY2JQ1AG.

Of course, this is an incorrect way to use the library, but it is quite misleading that it returns a value that looks like a deviceId of sorts. In reality, the value is just hashing empty contents and returning this.

Another scenario where this happens is if the requested component is not working, for instance:

Console.WriteLine(
  new DeviceIdBuilder()
  .OnLinux(x => x.AddMotherboardSerialNumber())
  .ToString()
);

If the user does not have access to /sys/class/dmi/id/board_serial (or it does not exist) the result is again: WERC8GMRZGE196QVYK49JVXS4GKTWGF4CJDS6K54JPCHPY2JQ1AG.

For my uses, I have added this value as a "known bad value", but I think the library should return null or an empty string in this case, instead of returning a value that can be misinterpreted as a valid deviceId.