Make it possible to specify a default rerun filter

[recht]

No description provided.

[boxcla]

Hi @recht, thanks for the pull request. Before we can merge it, we need you to sign our Contributor License Agreement. You can do so electronically here: http://opensource.box.com/cla

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[aikrasnov]

Ping. @recht can we merge it? It would be nice

[CLAassistant]

Thank you for your submission! We really appreciate it. Like many open source projects, we ask that you sign our Contributor License Agreement before we can accept your contribution.
_{You have signed the CLA already but the status is still pending? Let us recheck it.}

[cclauss]

Please rebase or close this pull request. Tox is now running again under GitHub Actions.

• https://github.com/box/flaky/actions