Another regression defect in 5.2.120.  Receive spares goods in completely broken and unable to save result due to journal error.

Now fixed : 5.2 code was incorrectly using 'internal' tax code to model a spares goods in txn. Definition of 'internal' refined as part of 5.3 work and this broke this workflow. Reviewed all other code paths incase of other examples of this; confident goods in was only problem.