WQS: Add unit tests from Wikidata translator

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The Zotero Wikidata translator, as proposed here does the reverse of Wikidata QuickStatements exporter, so it should be possible to round-trip export and import. As far as I understand

• the translator does RDF/XML => Zotero
• the exporter does Zotero => QuickStatements

Given a QuickStatements to RDF/XML mapping we could use unit tests for both translator and exporter, right? Maybe @maxlath is interested in a QuickStatements parser/writer in JavaScript, but the format is easy to parse anyway.

Sure this issue has no top priority, I just wanted to note the idea.

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This issue is not solved, the existing unit tests only cover the QuickStatements exporter one way. The Zotero-to-Wikiata exporter contains its own test cases. Both can be combined to ensure test round-tripping import and export.

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There is also CitationJS Wikidata parser to test against.