`Run tox` step fails intermittently without a trace of what is going on

[fnordahl]

2022-02-09 13:36:19.065087 | TASK [Run tox]
2022-02-09 14:20:17.207344 | focal-medium | ERROR
2022-02-09 14:20:17.207940 | focal-medium | {
2022-02-09 14:20:17.208040 | focal-medium |   "delta": "0:43:57.504643",
2022-02-09 14:20:17.208155 | focal-medium |   "end": "2022-02-09 14:20:17.141640",
2022-02-09 14:20:17.208314 | focal-medium |   "msg": "non-zero return code",
2022-02-09 14:20:17.208405 | focal-medium |   "rc": 1,
2022-02-09 14:20:17.208485 | focal-medium |   "start": "2022-02-09 13:36:19.636997"
2022-02-09 14:20:17.208595 | focal-medium | }