flaky test in macos

main branch and 0.3 main 
```
%%% quicer_connection_SUITE ==> suite_reg.tc_conn_client_bad_cert: FAILED
%%% quicer_connection_SUITE ==> {test_case_failed,{run_error,{test_case_failed,"server still running"}}}
........................................................Testing lib.quicer: *** SKIPPED test case 216 of 323 ***
```