use patch instead of replace to test the dry-run option

[cpanato]

What type of PR is this?

/kind failing-test

What this PR does / why we need it:

Was observing some jobs for other fixes we have been changing and notice this test is failing a lot

can see in this job, for example, https://testgrid.k8s.io/sig-release-master-informing#capg-conformance-v1alpha3-k8s-master and https://testgrid.k8s.io/sig-release-master-informing#capa-conformance-v1alpha3-k8s-master&width=30

The test creates a pod and get the JSON spec right away and then replaces the image to perform the actual test.
However, sometimes might have other reconciliation in the cluster that changes the resource version and when the test try to apply the change this the spec is old and the test fail.
Waiting for the pod to be running maybe is a good option and then get the spec and perform the test.
Test locally and did not reproduce the issue with this change.

error in the job:

Kubernetes e2e suite: [sig-cli] Kubectl client Kubectl server-side dry-run should check if kubectl can dry-run update Pods [Conformance] expand_less | 2s
-- | --
/workspace/kubernetes/_output/local/go/src/k8s.io/kubernetes/test/e2e/framework/framework.go:629 Oct 22 21:18:04.003: Unexpected error:     
<exec.CodeExitError>: {       
  Err: {          
   s: "error running /workspace/kubernetes/_output/bin/kubectl --server=https://localhost:6443 --kubeconfig=/workspace/.kube/config --namespace=kubectl-4231 replace -f - --dry-run=server:\nCommand stdout:\n\nstderr:\nError from server (Conflict): error when replacing \"STDIN\": Operation cannot be fulfilled on pods \"e2e-test-httpd-pod\": the object has been modified; please apply your changes to the latest version and try again\n\nerror:\nexit status 1",        
 },         
Code: 1,    
 }     

error running /workspace/kubernetes/_output/bin/kubectl --server=https://localhost:6443 --kubeconfig=/workspace/.kube/config --namespace=kubectl-4231 replace -f - --dry-run=server:     Command stdout:          stderr:     Error from server (Conflict): error when replacing "STDIN": Operation cannot be fulfilled on pods "e2e-test-httpd-pod": the object has been modified; please apply your changes to the latest version and try again          error:     exit status 1 occurred /workspace/kubernetes/_output/local/go/src/k8s.io/kubernetes/test/e2e/framework/util.go:592

Which issue(s) this PR fixes:

Fixes: #95832

Special notes for your reviewer:

Does this PR introduce a user-facing change?:

NONE

Additional documentation e.g., KEPs (Kubernetes Enhancement Proposals), usage docs, etc.:

[cpanato]

/assign @soltysh

[mkumatag]

/lgtm

[mkumatag]

/priority important-soon

[dims]

/assign @deads2k

@soltysh @deads2k one line PR, so should be quick :)

[mkumatag]

/assign @deads2k

@soltysh @deads2k one line PR, so should be quick :)

We need this badly as we are hitting with this issue for every run, it will be great if someone can help us merging this asap

[deads2k]

I'd like to know why pods were chosen. A conflict error looks to be correct in cases where there is a conflict. It seems more correct to me to use an unconditional update if that's what you want or to choose a resource with less contention.

/assign @apelisse

[deads2k]

I'd like to know why pods were chosen. A conflict error looks to be correct in cases where there is a conflict. It seems more correct to me to use an unconditional update if that's what you want or to choose a resource with less contention.

I'd suggest going with an unconditional update to avoid the conflict error, but keep the spirit of the test.

[apelisse]

@cpanato Would you mind updating with a patch rather than a replace so that you avoid the conflicts? Thanks.

[cpanato]

@apelisse make the change, thanks for your review PTAL

[apelisse]

Yeah, I think that's good and shouldn't fail like it did before.
/lgtm

[dims]

/assign @johnbelamaric

(for test/conformance/testdata/OWNERS)

[spiffxp]

/triage accepted
/approve
/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: cpanato, spiffxp

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Needs approval from an approver in each of these files:

• test/conformance/testdata/OWNERS [spiffxp]
• test/e2e/kubectl/OWNERS [spiffxp]

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[hh]

/test pull-kubernetes-node-e2e

[hh]

Keeping an eye on this as a dependency of #95832

[Riaankl]

/test pull-kubernetes-bazel-test