enable filterwarnings=error to prevent ResourceWarnings

[graingert]

Thanks for contributing to Selenium!
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Avoid large PRs, help reviewers by making them as simple and short as possible.

Description

Motivation and Context

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• I have read the contributing document.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have added tests to cover my changes.
• All new and existing tests passed.

[graingert]

Hmm I don't have permission to run CI despite having a merged PR #13329

[titusfortner]

Yes we have to approve PRs.
Can you fill out the template indicating what this does and why we want it?

[diemol]

I guess we can close it, we never heard back from @graingert.