Same idShort for SML and SMC ProductClassifications lead to misinterpretations

[twebermartins]

Issue: idShort for SML and SMC ProductClassifications lead to misinterpretations are the same
Expected: keep idShort [SML] ProductClassifications and change [SMC] ProductClassification**s** to [SMC] ProductClassification as it is a single entry

see page 7 UML diagram in
https://smt-repo.admin-shell-io.com/api/published-file?path=IDTA%2002003_2-0-1_Template_TechnicalData.pdf