The check for 'would limit' log message is triggered by sending at least
three messages within one second. However, in extremely slow conditions
(currently when running with clang+TSAN in CI), the individual queries
might take too much time to send enough of them within one second.
Since this is a pretty rare condition, let's just silently skip this
test in environments where a single query takes more than 500 ms, since
there's no way to perform the check under such conditions.
Closes#4082
d8997db5d5