Add supports for categorize test cases with TestNG Groups

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#### I'm submitting a ...
- feature request

#### What is the current behavior?

Recently, I came across the problem that I wasn't able to check the results of test case group wise when I executed the same test case in different groups in different Jenkins jobs.

Below is the scenario:
1. Test case **A** is a part of group UK and US.
2. Trigger Jenkins job **J** to execute test case **A** in Jenkins job **J1** as a part of UK and in Jenkins job **J2** as a part of US.
4. Copy allure artifacts of **J1** and **J2** in **J** and merge the report using allure Jenkins plugin.

**Results**: Jenkins job **J** merged test case **A** results as a history.

#### What is the expected behavior?

I want to see the execution results group-wise for clear understanding.

#### Please tell us about your environment:

No need to specify as its feature request.

Commencez par examiner l’intégration de TestNG et le scénario de merge Jenkins décrit dans l’issue. Déterminez comment l’appartenance aux groupes et les résultats fusionnés sont actuellement représentés, puis définissez des tests qui distinguent le même cas exécuté dans les groupes UK et US ; le travail est considéré comme terminé lorsque le rapport fusionné expose ces exécutions par groupe.

Rédigé par le modèle d'indexation à partir du texte de l'issue.