Add logs, stdout and stderr to the allure-pytest-bdd report

[IvanBuruyane]

Context

Currently allure report for the pytest-bdd framework doesn't include logs, stdout and stderr created during test run. It makes hard to understand what was the root cause of the test failure. In order to fix this I simply added the code from the allure-pytest listener that adds logs, stdout and stderr to the report. Here's a screenshot from the report with logs:

Checklist

• [x] Sign Allure CLA
• [x] Provide unit tests

[CLAassistant]

All committers have signed the CLA.

[IvanBuruyane]

@veryhappythings , @janza , @middagj. Please take a look at this MR. I've added some tests, plus I use the fork with this code for a long time on my project, and it works (you can see it on the screenshot). I would really appreciate if you approve this PR. Thanks beforehand.