E2E tests: remove console error check for branch test

What does this MR do and why?

Remove check of console errors from browser_ui/3_create/repository/branch_with_unusual_name_spec.rb, as this check is picking up unrelated errors in prod. This test should still fail if the branch isn't created correctly without this check.

Resolves #403573 (closed)

Basically this check would make an test fail in production and I think it was put in place for debugging purposes

How to set up and validate locally

QA_LOG_LEVEL=DEBUG QA_GITLAB_URL=http://192.168.4.31:3000 bundle exec rspec qa/specs/features/browser_ui/3_create/repository/branch_with_unusual_name_spec.rb

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