Investigate possible race condition in fqgrep

[nh13]

One of the github actions unit tests failed on test_reads_when_count_false. It passed when re-run, so this gives me pause.

I have run it locally and seen a sporadic failure:

for i in $(seq 1000)
do
    echo on test $i
    cargo test &> run.log
    retval=$?
    grep "test result" run.log | sed 's/^/  /';
    if [ "$retval" == "0" ]; then
        echo Test $i passed
        rm run.log
    else
        echo Test $i failed, check run.log
        exit 1;
    fi
done

I wonder if there's some type of race condition or out of order output.