Intermittent failure in kafka_server_fixture read_from_ntp_max_bytes

[travisdowns]

Failed in e.g. the CI for this backport: https://github.com/redpanda-data/redpanda/pull/7351

I could reproduce locally:

i=0; while ../bin/test_kafka_server_fixture_rpunit --run_test=read_from_ntp_max_bytes -- -c 1 >& log-$i; do i=$((i+1)); done

This almost always failed before 20 attempted runs on my local host.

Failure message:

unknown location(0): [4;31;49mfatal error: in "read_from_ntp_max_bytes": std::runtime_error: ntp {kafka/my_topic_0/0}: log offset -9223372036854775808 is outside the translation range (starting at 0)[0;39;49m
/home/tdowns/dev/redpanda/src/v/kafka/server/tests/fetch_test.cc(158): [1;36;49mlast checkpoint: redpanda_thread_fixture::read_from_ntp_max_bytes()[0;39;49m