Need clear error message when `verifyContribution` fails

[baumstern]

phase2cli print following message:

✔ Your contribution will start soon ⌛

- Circuit # 1 (Contribution Steps)
✔ Contribution #00000 correctly downloaded
✔ Contribution #00001 computation took 00:10:03
✔ Contribution #00001 correctly saved on storage
🕛  Verifying your contribution...
node:internal/process/promises:279
            triggerUncaughtException(err, true /* fromPromise */);
            ^

[FirebaseError: internal] {
  code: 'functions/internal',
  customData: undefined,
  details: undefined
}
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.
error Command failed with exit code 1.
info Visit https://yarnpkg.com/en/docs/cli/run for documentation about this command.

The log of verifycontribution is like following:

DEBUG 2023-02-06T20:29:57.858724Z Callable request verification passed
DEBUG 2023-02-06T20:29:58.922247Z [DEBUG] Ceremony document zll83rWBWy5y1iwQ2Zth okay
DEBUG 2023-02-06T20:29:58.922298Z [DEBUG] Circuit document n6iqpriO4tmNjOe7U76Y okay
DEBUG 2023-02-06T20:29:58.922490Z [DEBUG] Participant document vXnTUrTucnXDDpNVzXT14Xd2d6z1 okay
DEBUG 2023-02-06T20:31:45.172322Z [DEBUG] pot/powersOfTau28_hez_final_22.ptau downloaded
DEBUG 2023-02-06T20:33:05.211742Z [DEBUG] circuits/multiplier2/contributions/multiplier2_00000.zkey downloaded
DEBUG 2023-02-06T20:34:23.767498Z [DEBUG] circuits/multiplier2/contributions/multiplier2_00001.zkey downloaded
INFO 2023-02-06T20:34:23.767610Z [INFO] Downloads from storage completed
INFO 2023-02-06T20:38:41.756248Z [INFO] Contribution is valid
INFO 2023-02-06T20:38:41.756338Z [INFO] Verification computation time 257988 ms
ERROR 2023-02-06T20:38:41.837497Z [httpRequest.requestMethod: POST] [httpRequest.status: 500] [httpRequest.responseSize: 818 B] [httpRequest.latency: 527.339 s] [httpRequest.userAgent: node-fetch 1.0] https://[redacted]/
DEFAULT 2023-02-06T20:38:42.864857Z Error: ENOENT: no such file or directory, open '/tmp/multiplier2_00001.zkey'