Be more thorough when deciding whether a volume is mounted or not.

[cphvmware]

What this PR does / why we need it:
On Windows, use of isLikelyNotMountPoint() is not a reliable way to decide whether a mount point is usable. This change adds additional logic to get a reliable result.

Testing done:
#2004 (comment)

Special notes for your reviewer:

Release note:

Be more thorough when deciding whether a volume is mounted or not

[k8s-ci-robot]

Hi @cphvmware. Thanks for your PR.

I'm waiting for a kubernetes-sigs member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[divyenpatel]

/ok-to-test

[cphvmware]

Testing done:
`Power Off/Power On:

...after a while...

kubo@BYgyz7NY8iIQz:~$ kubectl get pods -o wide
NAME    READY   STATUS    RESTARTS            AGE   IP            NODE                                                     NOMINATED NODE   READINESS GATES
web-0   1/1     Running   1 (<invalid> ago)   20m   100.96.3.16   tkg-vc-antrea-md-0-windows-containerd-5c7888d6bc-wdnvm   <none>           <none>

Delete pod:

kubectl delete pods web-0 --grace-period=0 --force
warning: Immediate deletion does not wait for confirmation that the running resource has been terminated. The resource may continue to run on the cluster indefinitely.
pod "web-0" force deleted

...after a while...

kubo@BYgyz7NY8iIQz:~$ kubectl get pods -o wide
NAME    READY   STATUS    RESTARTS   AGE   IP            NODE                                                     NOMINATED NODE   READINESS GATES
web-0   1/1     Running   0          86s   100.96.3.17   tkg-vc-antrea-md-0-windows-containerd-5c7888d6bc-wdnvm   <none>           <none>

`

[divyenpatel]

/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cphvmware, divyenpatel

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• OWNERS [divyenpatel]

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