Pin pytest-bdd to keep tests working

[micahellison]

This PR pins pytest-bdd to 7.1.1 to keep tests from breaking due to #1875. It doesn't fix the problem but it will at least allow tests to run on PRs.

Checklist

• I have read the contributing doc.
• I have included a link to the relevant issue number.
• I have checked to ensure there aren't other open pull requests
  for the same issue.
• I have written new tests for these changes, as needed.

[micahellison]

It looks like tox and poetry use different version resolvers for pytest plugins in particular. I'm not sure how to actually make this work in our test runner. Closing this for now to avoid confusion. I think it's probably a better use of time to just fix the root cause by importing fixtures differently to appease pytest-bdd 7.1.2.