Feature/increase test coverage

[GezimSejdiu]

This PR increases the coverage to 34% and does some other implementation (e.g. alignment of Flink implementation of quality assessment with the ones implemented in Spark, rdf tensor representation) and further cleanups and refactoring of Flink module.

Best regards,

[coveralls]

Pull Request Test Coverage Report for Build 210

• 68 of 212 (32.08%) changed or added relevant lines in 20 files are covered.
• 3 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+4.3%) to 34.082%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/completeness/InterlinkingCompleteness.scala	0	1	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/completeness/PropertyCompleteness.scala	0	1	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/completeness/SchemaCompleteness.scala	0	1	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/licensing/MachineReadableLicense.scala	0	4	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/stats/RDFStatistics.scala	1	5	20.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/licensing/HumanReadableLicense.scala	0	6	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/relevancy/CoverageDetail.scala	0	7	0.0%
sansa-rdf-spark/src/main/scala/net/sansa_stack/rdf/spark/model/package.scala	18	26	69.23%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/relevancy/CoverageScope.scala	0	9	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/reprconciseness/QueryParamFreeURIs.scala	0	9	0.0%

Files with Coverage Reduction	New Missed Lines	%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/completeness/InterlinkingCompleteness.scala	1	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/qualityassessment/metrics/syntacticvalidity/XSDDatatypeCompatibleLiterals.scala	1	0.0%
sansa-rdf-flink/src/main/scala/net/sansa_stack/rdf/flink/stats/RDFStatistics.scala	1	3.7%

Totals
Change from base Build 207:	4.3%
Covered Lines:	1488
Relevant Lines:	4366

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💛 - Coveralls

[dgraux]

Hi @GezimSejdiu
Wow that's a lot of contribution! 👍
Thank you… 😺