Unrelated but fyi tox 4 has `-f` supported out of the box. We should probably update all of our test workflows to use that, and you don't need tox-factor

[ocelotl]

          Unrelated but fyi tox 4 has `-f` supported out of the box. We should probably update all of our test workflows to use that, and you don't need tox-factor

Originally posted by @aabmass in #3450 (comment)

[iurisilvio]

For reference: rpkilby/tox-factor#18