Fix flaky test downstream_sv1::diff_management::test::test_diff_management

[jbesraa]

Noisy test. Produces a lot of false alarms

https://github.com/stratum-mining/stratum/actions/runs/9601943467/job/26481865946?pr=968#step:7:422

 running 4 tests
test downstream_sv1::downstream::tests::gets_difficulty_from_target ... ok
test proxy::bridge::test::test_version_bits_insert ... ok
test downstream_sv1::diff_management::test::test_converge_to_spm_from_low ... ok
test downstream_sv1::diff_management::test::test_diff_management ... FAILED
failures:
---- downstream_sv1::diff_management::test::test_diff_management stdout ----
thread 'downstream_sv1::diff_management::test::test_diff_management' panicked at translator/src/lib/downstream_sv1/diff_management.rs:349:9:
Calculated shares per minute are outside the 99% confidence interval. Error: 4776.132, Error margin: 189.73665961010275, 5776.132
note: run with `RUST_BACKTRACE=1` environment variable to display a backtrace
failures:
    downstream_sv1::diff_management::test::test_diff_management
test result: FAILED. 3 passed; 1 failed; 0 ignored; 0 measured; 0 filtered out; finished in 16.02s
error: test failed, to rerun pass `-p translator_sv2 --lib`

[plebhash]

closed via #995

[jbesraa]

@plebhash I think we should reopen this issue as the test is not fixed. I would suggest to #[ignore] the test for now.

[Fi3]

about this test I use a z_score of 2.576 total runtime of 40 seconds and measure hash rate of 10 seconds.
With this values on my machine it pass almost all the time, I saw it fail just one time.
z_score I use for 99%, from what I saw more then 10 second do not improve the estimation, I always get the same error range also if I double or quadruple it on average. 40 seconds empirically are the shortest amount of time that almost never fail, ofc that on my machine dunno but maybe is relevant.

[pavlenex]

Do you guys want me to re-open this issue?

[plebhash]

#1074 is disabling the test as a temporary solution

we should eventually try to come up with a more sustainable fix to this problem

[GitGab19]

Reopening it, as agreed here