release-26.2: backup: TestBackupCompactionExecLocality failed

backup.TestBackupCompactionExecLocality [failed](https://mesolite.cluster.engflow.com/invocations/default/497e9747-147a-4250-a1ab-39bd7163b09e?testReportRun=2&testReportShard=15&testReportAttempt=1#targets-Ly9wa2cvYmFja3VwOmJhY2t1cF90ZXN0) on release-26.2 @ [0cd9a94821abf8eed917ee2a6edd8a2591a67990](https://github.com/cockroachdb/cockroach/commits/0cd9a94821abf8eed917ee2a6edd8a2591a67990):

```
=== RUN TestBackupCompactionExecLocality
test_log_scope.go:172: test logs captured to: outputs.zip/logTestBackupCompactionExecLocality2632324701
test_log_scope.go:82: use -show-logs to present logs inline
test_server_shim.go:95: cluster virtualization disabled due to issue: #142798 (expected label: C-test-failure)
test_server_shim.go:638: DRPC is enabled (via testserver factory defaults)
compaction_test.go:997: error executing query="BACKUP DATABASE data INTO LATEST IN ('nodelocal://4/pin-tier') " args=[]: pq: rpc error: code = Canceled desc = context canceled
testutils.go:368: no Invalid Descriptors
panic.go:615: -- test log scope end --
test logs left over in: outputs.zip/logTestBackupCompactionExecLocality2632324701
--- FAIL: TestBackupCompactionExecLocality (29.44s)
=== RUN TestBackupCompactionExecLocality/pin-tier
testing.go:1811: test executed panic(nil) or runtime.Goexit: subtest may have called FailNow on a parent test
--- FAIL: TestBackupCompactionExecLocality/pin-tier (14.77s)
```

Parameters:
- attempt=1
- deadlock=true
- run=2
- shard=15
Help

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

/cc @cockroachlabs/disaster-recovery

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

Jira issue: CRDB-68496

Start at compaction_test.go:997 and run backup.TestBackupCompactionExecLocality, then inspect the linked test report and captured outputs.zip logs for the context-canceled BACKUP query. Done is not specified beyond resolving this failure and obtaining a passing test.

Written by the indexing model from the issue text.