E2E: Reset browser session between each test

What does this MR do and why?

Reset browser session between each test to remove state leek that can happen through leftover cookies etc. (reset method does not clear localStorage so might have to be added in the future if proves to be a problem)

Fixes error randomly failing the whole test job without ability to retry when running in parallel.

Closes: gitlab-org/quality/quality-engineering/team-tasks#3087 (closed)

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