Add "update" verb to pdb resource of mpi-job

[terrytangyuan]

This is required if gang scheduling is enabled. See MPI-Operator's RBAC here that requires "update" for pdb resource.

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This change is 

[pdmack]

/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: pdmack

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[pdmack]

/test all

[terrytangyuan]

/retest

[pdmack]

Meh, same error. @terrytangyuan can you try rebasing please? I'm not sure which change that might be.

[terrytangyuan]

/retest

[terrytangyuan]

@pdmack Just rebased.

[pdmack]

/retest

[terrytangyuan]

Hmm. This is a simple change. The failing tests are related to Argo. Is there another way to get this merged?

[pdmack]

/test all

[pdmack]

/retest

[pdmack]

/retest

[pdmack]

/lgtm

[pdmack]

Sorry that took so long @terrytangyuan.

[terrytangyuan]

@pdmack No worries. Thanks for the help! We definitely should look into the root cause for this though.

[pdmack]

Well, the retests were due to some quota issues in the kubeflow test infra. We're working on improved maintenance there, both human and automated.

[terrytangyuan]

Sounds good. Thanks!