roachtest: costfuzz/rand-tables failed

**Note:** This build has runtime assertions enabled. If the same failure was hit in a run without assertions enabled, there should be a similar failure without this message. If there isn't one, then this failure is likely due to an assertion violation or (assertion) timeout.

roachtest.costfuzz/rand-tables [failed](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_Roachtests_RoachtestNightlyGcePrivateBazel/21520406?buildTab=log) with [artifacts](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_Roachtests_RoachtestNightlyGcePrivateBazel/21520406?buildTab=artifacts#/costfuzz/rand-tables) on master @ [5d7eb2e1fee29048322d2533eccd0362ba67c0a8](https://github.com/cockroachdb/cockroach/commits/5d7eb2e1fee29048322d2533eccd0362ba67c0a8):

Failed with:

```
(query_comparison_util.go:501).runOneRoundQueryComparison: internal error while running perturbed statement. 2614 statements run: pq: internal error: unhandled op distribute
test artifacts and logs in: /artifacts/costfuzz/rand-tables/run_1
```
Cluster Node to Ip Mapping:
| Node | Public IP | Private IP |
| --- | --- | --- |
| teamcity-21520406-1789624655-09-n1cpu4-0001 | | 10.91.98.238 |

Parameters:
- arch=amd64
- cloud=gce
- coverageBuild=false
- cpu=4
- diskCount=0
- encrypted=false
- metamorphicLeases=default
- metamorphicWriteBuffering=true
- runtimeAssertionsBuild=true
Help

See: [roachtest README](https://github.com/cockroachdb/cockroach/blob/master/pkg/cmd/roachtest/README.md)

See: [How To Investigate \(internal\)](https://cockroachlabs.atlassian.net/l/c/SSSBr8c7)

See: [Grafana](https://go.crdb.dev/roachtest-grafana/teamcity-21520406/costfuzz-rand-tables/1789625678630/1789628818363)

See: [Datadog Logs](https://us5.datadoghq.com/logs?query=service%3Aroachtest+%40cluster%3Ateamcity-21520406-1789624655-09-n1cpu4&from_ts=1789625678630&to_ts=1789628818363&live=false&storage=flex_tier)

[Improve this report!](https://github.com/cockroachdb/cockroach/tree/master/pkg/cmd/bazci/githubpost/issues)

Jira issue: CRDB-68468

Start with query_comparison_util.go at runOneRoundQueryComparison around line 501, then inspect the costfuzz/rand-tables artifacts and logs under /artifacts/costfuzz/rand-tables/run_1. Investigate the unhandled distribute operation in the perturbed statement path. Done means the failure is understood and the rand-tables roachtest completes without this internal error.

Written by the indexing model from the issue text.