LPS-50671

Rename JournalArticle.StructureId to JournalArticle.StructureKey to avoid confusions but keep database column name in order to be able to backport this to 6.2.x
At LPS-31163, I do rest of changes to master to change database column to new structureKey name, see pull: https://github.com/juliocamarero/liferay-portal/pull/3067