Also make it flakier in longtest mode by burning through more
ephemeral ports. (Burning through the ports raised the failure rate
for me locally enough to reliably reproduce the failure in #65175 with
-count=10.)
Fixes #65175 (I hope).
Change-Id: I5f5b68b6bf6a6aa92e66f0288078817041656a3e
Reviewed-on: https://go-review.googlesource.com/c/go/+/557177 Reviewed-by: Damien Neil <dneil@google.com>
Auto-Submit: Bryan Mills <bcmills@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>