roachtest: ssh_problem failed

roachtest.ssh_problem [failed](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_RoachtestNightlyGceBazel/17613227?buildTab=log) with [artifacts](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_RoachtestNightlyGceBazel/17613227?buildTab=artifacts#/backup-restore/mixed-version) on release-24.1.7-rc @ [62d13cef08f5a5b487216dc9c996f01a866f1341](https://github.com/cockroachdb/cockroach/commits/62d13cef08f5a5b487216dc9c996f01a866f1341):

```
test backup-restore/mixed-version failed: (test_runner.go:803).func4: full command output in run_064804.275350005_n1-5_mkdir-p-lib.log: error persisted after 3 attempts: _potential_ SSH flake (``ssh -vvv`` log retained in /artifacts/backup-restore/mixed-version/run_1/ssh/ssh_064804.292689922_n4_mkdir-p-lib.log): TRANSIENT_ERROR(ssh_problem): exit status 255 [owner=test-eng]
```

Parameters:
- ROACHTEST_arch=amd64
- ROACHTEST_cloud=gce
- ROACHTEST_coverageBuild=false
- ROACHTEST_cpu=4
- ROACHTEST_encrypted=false
- ROACHTEST_fs=ext4
- ROACHTEST_localSSD=true
- ROACHTEST_runtimeAssertionsBuild=false
- ROACHTEST_ssd=0
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-17613227/backup-restore-mixed-version/-62135596800000/-62135596680000)

Same failure on other branches

- #134034 roachtest: ssh_problem failed [O-roachtest O-robot X-infra-flake branch-release-23.1.29-rc]
- #133924 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.2.5-rc]
- #132980 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.3]
- #131724 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.2.4-rc]
- #131720 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.1.6-rc]
- #129915 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-23.1.26-rc]
- #127118 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.2]
- #122095 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.1]
- #112310 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-23.2]
- #108264 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-23.1]

/cc @cockroachdb/test-eng

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

Jira issue: CRDB-44036