release-26.3.0-rc: sql: TestRelocateNonVoters failed

sql.TestRelocateNonVoters [failed](https://mesolite.cluster.engflow.com/invocations/default/ff8d2d64-3a5a-4274-a996-48e7c7d15aaa?testReportRun=9&testReportShard=1&testReportAttempt=1#targets-Ly9wa2cvc3FsOnNxbF90ZXN0) on release-26.3.0-rc @ [6fc76e440f10d42bf6336089d8df503603f4894a](https://github.com/cockroachdb/cockroach/commits/6fc76e440f10d42bf6336089d8df503603f4894a):

```
=== RUN TestRelocateNonVoters
test_log_scope.go:172: test logs captured to: outputs.zip/logTestRelocateNonVoters3536651847
test_log_scope.go:82: use -show-logs to present logs inline
multitenant_admin_function_test.go:936: -- test log scope end --
test logs left over in: outputs.zip/logTestRelocateNonVoters3536651847
--- FAIL: TestRelocateNonVoters (63.67s)
=== RUN TestRelocateNonVoters/ALTER_RANGE_RELOCATE_NONVOTERS
multitenant_admin_function_test.go:186: condition failed to evaluate within 45s: from multitenant_admin_function_test.go:194: waiting for 1 ranges with LEARNER replicas to clear

goroutine dump: /mnt/engflow/worker/work/0/exec/bazel-out/k8-fastbuild/testlogs/pkg/sql/sql_test/shard_1_of_16_run_9_of_10/test.outputs/goroutine_dump_3900214753.txt
--- FAIL: TestRelocateNonVoters/ALTER_RANGE_RELOCATE_NONVOTERS (54.41s)
```

Parameters:
- attempt=1
- run=9
- shard=1
Help

See also: [How To Investigate a Go Test Failure \(internal\)](https://cockroachlabs.atlassian.net/l/c/HgfXfJgM)

/cc @cockroachlabs/sql-foundations

[This test on roachdash](https://roachdash.crdb.dev/?filter=status:open%20t:.*TestRelocateNonVoters.*&sort=title+created&display=lastcommented+project) | [Improve this report!](https://github.com/cockroachdb/cockroach/tree/master/pkg/cmd/bazci/githubpost/issues)

Jira issue: CRDB-66144

Start by reproducing sql.TestRelocateNonVoters on release-26.3.0-rc at commit 6fc76e440f10d42bf6336089d8df503603f4894a, using the failure report and captured logs from outputs.zip/logTestRelocateNonVoters3536651847. Read the ALTER_RANGE_RELOCATE_NONVOTERS case in multitenant_admin_function_test.go, especially the wait at line 194. Done means the test completes without leaving learner replicas after relocation.

Written by the indexing model from the issue text.