feature: implement ListPodSandbox method of cri manager

[YaoZengzeng]

Signed-off-by: YaoZengzeng [email protected]

1.Describe what this PR did

fixes part of #420

2.Does this pull request fix one issue?

3.Describe how you did it

4.Describe how to verify it

Maybe the cri-tools is what you need.

We may use the following method to verify that we can list sandboxes:

// Now we must ensure the sandbox image has already exists.
[root@pouch-test cri-tools]# pouch pull k8s.gcr.io/pause-amd64:3.0
[root@pouch-test cri-tools]# cat sandbox-config.json
{
    "metadata": {
        "name": "nginx-sandbox",
        "namespace": "default",
        "attempt": 1,
        "uid": "hdishd83djaidwnduwk28bcsb"
    },
    "linux": {
    }
}
[root@pouch-test cri-tools]# crictl runs sandbox-config.json
008cc69c9c9c8e9c4d78aa8d6c528e21ab26affdc64748f631fb5dcb59963216
[root@pouch-test cri-tools]# crictl sandboxes
SANDBOX ID          CREATED             STATE               NAME                NAMESPACE           ATTEMPT
008cc69c9c9c8       48 years ago        SANDBOX_READY       nginx-sandbox       default             1

5.Special notes for reviews

[codecov-io]

Codecov Report

Merging #551 into master will decrease coverage by 0.04%.
The diff coverage is 12.5%.

@@            Coverage Diff             @@
##           master     #551      +/-   ##
==========================================
- Coverage   14.16%   14.12%   -0.05%     
==========================================
  Files          64       64              
  Lines        3226     3278      +52     
==========================================
+ Hits          457      463       +6     
- Misses       2722     2768      +46     
  Partials       47       47

Impacted Files	Coverage Δ
daemon/mgr/cri.go	0% <0%> (ø)	⬆️
daemon/mgr/cri_utils.go	36.36% <15.38%> (-4.82%)	⬇️

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[YaoZengzeng]

@allencloud PTAL.

[allencloud]

Just use TestToCriSandboxState? This is sufficient, I think.

[YaoZengzeng]

@allencloud updated.

[allencloud]

LGTM