1475 add descriptive stats to all tasks v2 (#1482)

* add code for comupting number of qrels

* BibleNLPBitextMining descriptive stats added

* SwissJudgementClassification descriptive stats added

* VoyageMMarcoReranking descriptive stats added

* WebLINXCandidatesReranking descriptive stats added

* MultiEURLEXMultilabelClassification descriptive stats added

* MIRACLReranking descriptive stats added

* MindSmallReranking descriptive stats added

* updated test_TaskMetadata

* fix test

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Co-authored-by: Imene Kerboua <[email protected]>
Co-authored-by: Imene Kerboua <[email protected]>
Co-authored-by: Roman Solomatin <[email protected]>