basalt-26.3: backup: TestBackupRestorePartitionedMergeDirectories failed

backup.TestBackupRestorePartitionedMergeDirectories [failed](https://mesolite.cluster.engflow.com/invocations/default/d2159fb4-17bf-4f8c-9256-173ede54f65c?testReportRun=3&testReportShard=32&testReportAttempt=1#targets-Ly9wa2cvYmFja3VwOmJhY2t1cF90ZXN0) on basalt-26.3 @ [edc226e9d007d4a208c831af595863f67e923ebe](https://github.com/cockroachdb/cockroach/commits/edc226e9d007d4a208c831af595863f67e923ebe):

```
=== RUN TestBackupRestorePartitionedMergeDirectories
test_log_scope.go:172: test logs captured to: outputs.zip/logTestBackupRestorePartitionedMergeDirectories955524157
test_log_scope.go:82: use -show-logs to present logs inline
test_server_shim.go:168: automatically injected an external process virtual cluster under test; see comment at top of test_server_shim.go for details.
backup_test.go:1011: condition failed to evaluate within 2m0s: expected job status succeeded, but got running

goroutine dump: /mnt/engflow/worker/work/0/exec/bazel-out/k8-fastbuild/testlogs/pkg/backup/backup_test/shard_32_of_48_run_3_of_3/test.outputs/goroutine_dump_1501352709.txt
testutils.go:385: no Invalid Descriptors
panic.go:694: -- test log scope end --
test logs left over in: outputs.zip/logTestBackupRestorePartitionedMergeDirectories955524157
--- FAIL: TestBackupRestorePartitionedMergeDirectories (1259.92s)
```

Parameters:
- attempt=1
- race=true
- run=3
- shard=32
Help

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

Same failure on other branches

- #173816 backup: TestBackupRestorePartitionedMergeDirectories failed [A-disaster-recovery C-test-failure O-robot P-3 T-disaster-recovery branch-master]

/cc @cockroachlabs/disaster-recovery

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Jira issue: CRDB-68162