roachtest: ssh_problem 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.ssh_problem [failed](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_RoachtestNightlyAwsBazel/18923385?buildTab=log) with [artifacts](https://teamcity.cockroachdb.com/buildConfiguration/Cockroach_Nightlies_RoachtestNightlyAwsBazel/18923385?buildTab=artifacts#/http-register-routes/mixed-version) on release-25.1.1-rc @ [9041a5d800f253e1fe6a87516a20d63c68c42519](https://github.com/cockroachdb/cockroach/commits/9041a5d800f253e1fe6a87516a20d63c68c42519):

```
test http-register-routes/mixed-version failed: (test_runner.go:847).func4: cluster.PutE: put "/go/src/github.com/cockroachdb/cockroach/bin/cockroach-ea.linux-amd64" failed: TRANSIENT_ERROR(ssh_problem): ~ scp -r -C -o StrictHostKeyChecking=no -o ConnectTimeout=10 -i /home/roach/.ssh/id_rsa /go/src/github.com/cockroachdb/cockroach/bin/cockroach-ea.linux-amd64 ubuntu@18.119.235.34:./cockroach
Warning: Permanently added '18.119.235.34' (ECDSA) to the list of known hosts.
: signal: killed [owner=test-eng]
```

Parameters:
- arch=amd64
- cloud=aws
- coverageBuild=false
- cpu=4
- encrypted=false
- fs=ext4
- localSSD=true
- runtimeAssertionsBuild=true
- 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)

_Grafana is not yet available for aws clusters_

Same failure on other branches

- #141918 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.1.14-rc]
- #141691 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.3.7-rc]
- #140793 roachtest: ssh_problem failed [O-roachtest O-robot O-rsg T-testeng X-infra-flake branch-release-25.1.0-rc]
- #140365 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.1.12-rc]
- #140343 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.3.5-rc]
- #140341 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.2.10-rc]
- #140099 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-23.2.20-rc]
- #139629 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.1.11-rc]
- #139626 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.3.4-rc]
- #139623 roachtest: ssh_problem failed [O-roachtest O-robot T-testeng X-infra-flake branch-release-24.2.9-rc]

/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-48097