roachtest: restart/down-for-2m failed

[cockroach-teamcity]

roachtest.restart/down-for-2m failed with artifacts on master @ 63679e7bf4a0244c6e46381751543cfe3f32388c:

		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/vendor/golang.org/x/sync/errgroup/errgroup.go:54 +0x66
		  |
		  | goroutine 4167 [runnable]:
		  | golang.org/x/sync/errgroup.(*Group).Go.func1(0xc004533950, 0xc0045e3ce0)
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/vendor/golang.org/x/sync/errgroup/errgroup.go:54 fp=0xc001ca6fd0 sp=0xc001ca6fc8 pc=0x12dd3e0
		  | runtime.goexit()
		  | 	/usr/local/go/src/runtime/asm_amd64.s:1371 +0x1 fp=0xc001ca6fd8 sp=0xc001ca6fd0 pc=0x4c5cc1
		  | created by golang.org/x/sync/errgroup.(*Group).Go
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/vendor/golang.org/x/sync/errgroup/errgroup.go:54 +0x66
		  | Error: SSH_PROBLEM: exit status 255
		  | (1) SSH_PROBLEM
		  | Wraps: (2) Node 1. Command with error:
		  |   | ``````
		  |   | ./cockroach workload run tpcc --warehouses=100 --tolerate-errors --wait=false --duration=2m0s
		  |   | ``````
		  | Wraps: (3) exit status 255
		  | Error types: (1) errors.SSH (2) *hintdetail.withDetail (3) *exec.ExitError
		  |
		  | stdout:
		  | Initializing 1000 connections...
		  | Initializing 0 idle connections...
		  | Initializing 1000 workers and preparing statements...
		Wraps: (4) exit status 10
		Error types: (1) *withstack.withStack (2) *errutil.withPrefix (3) *cluster.WithCommandDetails (4) *exec.ExitError

	cluster.go:1249,context.go:89,cluster.go:1237,test_runner.go:866: dead node detection: /home/agent/work/.go/src/github.com/cockroachdb/cockroach/bin/roachprod monitor teamcity-3397107-1630563711-74-n3cpu4 --oneshot --ignore-empty-nodes: exit status 1 1: 11480
		3: dead (exit status 137)
		2: 11376
		Error: UNCLASSIFIED_PROBLEM: 3: dead (exit status 137)
		(1) UNCLASSIFIED_PROBLEM
		Wraps: (2) attached stack trace
		  -- stack trace:
		  | main.glob..func14
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachprod/main.go:1173
		  | main.wrap.func1
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachprod/main.go:281
		  | github.com/spf13/cobra.(*Command).execute
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/vendor/github.com/spf13/cobra/command.go:856
		  | github.com/spf13/cobra.(*Command).ExecuteC
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/vendor/github.com/spf13/cobra/command.go:960
		  | github.com/spf13/cobra.(*Command).Execute
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/vendor/github.com/spf13/cobra/command.go:897
		  | main.main
		  | 	/home/agent/work/.go/src/github.com/cockroachdb/cockroach/pkg/cmd/roachprod/main.go:2107
		  | runtime.main
		  | 	/usr/local/go/src/runtime/proc.go:225
		  | runtime.goexit
		  | 	/usr/local/go/src/runtime/asm_amd64.s:1371
		Wraps: (3) 3: dead (exit status 137)
		Error types: (1) errors.Unclassified (2) *withstack.withStack (3) *errutil.leafError

Reproduce

See: roachtest README

/cc @cockroachdb/kv-triage

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