chore: add Codecov test analytics

[thomasrockhu-codecov]

Description

Hi, Tom from Codecov here. I saw that you used Codecov already, and I thought you could benefit from catching any flaky or failed tests. We released a Test Analytics product that might be helpful and would love your feedback.

Related Issue

• Closes #
• Related to #

Checklist

• Checked that the pre-commit linting/style checks pass
• Included tests that prove the fix is effective or that the new feature works
• Added necessary documentation (docstrings and/or example notebooks)
• If you are a pro: each commit corresponds to a relevant logical change

Type of change

• New feature / enhancement
• Bug fix
• Documentation
• Maintenance
• Other (please specify):

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📚 Documentation preview 📚: https://pymc--7768.org.readthedocs.build/en/7768/

[welcome]

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[ricardoV94]

Not sure we need this, even the default codecov job is more annoying these days than not, as it fails to upload most times due to public token limitations

[thomasrockhu-codecov]

@ricardoV94 anything I can do to help with the coverage side of things? What seems to be the problem?