ccl/changefeedccl: TestChangefeedNemeses failed under stress

[cockroach-teamcity]

SHA: https://github.com/cockroachdb/cockroach/commits/8b5a5d6333a3d7ac7bdf96b7f90d6272247551cc

Parameters:

TAGS=
GOFLAGS=-race

To repro, try:

# Don't forget to check out a clean suitable branch and experiment with the
# stress invocation until the desired results present themselves. For example,
# using stress instead of stressrace and passing the '-p' stressflag which
# controls concurrency.
./scripts/gceworker.sh start && ./scripts/gceworker.sh mosh
cd ~/go/src/github.com/cockroachdb/cockroach && \
stdbuf -oL -eL \
make stressrace TESTS=TestChangefeedNemeses PKG=github.com/cockroachdb/cockroach/pkg/ccl/changefeedccl TESTTIMEOUT=5m STRESSFLAGS='-maxtime 20m -timeout 10m' 2>&1 | tee /tmp/stress.log

Failed test: https://teamcity.cockroachdb.com/viewLog.html?buildId=1835174&tab=buildLog

=== RUN   TestChangefeedNemeses
--- FAIL: TestChangefeedNemeses (903.45s)
    <autogenerated>:1: test logs captured to: /tmp/logTestChangefeedNemeses109509000
    <autogenerated>:1: use -show-logs to present logs inline

[knz]

dup #48459