When the network interface can't make any progress, it's probably
a good idea to yeild the task so that the wifi task may run and
proceed with actually sending/receiving data.

This seems to greatly improve response times, especially with low
tick_rate_hz values. At 100Hz, ping time goes down from 25ms to
<2ms. A simple http server test saw a response time reduction from
45ms to 6ms. At 1000Hz tick rate the gains are diminishing but
there are some small gains. I ran my tests on esp32s3.

This might also increase throughput. I have not tested that.
It also may have some unforseen adverse effects.

Ideally, we would have a more fine grained return value from
interface.poll() than a bool so we have a better idea if yeilding
is appropriate or not.

This reverts commit 77c437a.