allure plugin for robotframework-seleniumlibrary

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This could be an good example or part of a robot adapter
```python
import allure
from SeleniumLibrary import ScreenshotKeywords
from SeleniumLibrary.base import keyword, LibraryComponent

class AllureSeleniumPlugin(LibraryComponent):

@keyword
def capture_page_screenshot(self, filename='selenium-screenshot-{index}.png'):
path = ScreenshotKeywords(ctx=self.ctx).capture_page_screenshot(filename)
allure.attach.file(path, attachment_type=allure.attachment_type.PNG)
```

```robot
Library SeleniumLibrary plugins=AllureSeleniumPlugin
```

Commencez par l’exemple Python AllureSeleniumPlugin proposé et son point d’entrée capture_page_screenshot. Vérifiez comment le paramètre de Robot Framework Library transmet plugins=AllureSeleniumPlugin, puis déterminez la portée requise de l’intégration. Done doit fournir un plugin SeleniumLibrary utilisable qui joint les captures d’écran de page capturées aux rapports Allure.

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