Deal with EINTR in net timeout tests

We've seen sporadic QE failures in the timeout tests on this assertion:

    assert!(kind == ErrorKind::WouldBlock || kind == ErrorKind::TimedOut);

So there's an error, but not either of the expected kinds.  Adding a
format to show the kind revealed `ErrorKind::Interrupted` (`EINTR`).

For the cases that were using `read`, we can just use `read_exact` to
keep trying after interruption.  For those using `recv_from`, we have to
manually loop until we get a non-interrupted result.

0 files changed, 0 insertions, 0 deletions