Add default ulimit test for gen kube

[umohnani8]

Add a test for generate kube to verify that the ulimit
annotation is not set for the default case when the user
doesn't set any ulimits.

Fixes #18555
Implementation was done in #18721 and this PR adds a regression test.

Does this PR introduce a user-facing change?

None

[openshift-ci]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: umohnani8

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [umohnani8]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[Luap99]

I think the current way of setting default ulimits is just broken, see #18714 and #18696.
Instead of keeping this it is IMO better to move setting the default limits down in libpod and set it on each start. Then we do not alter ctr.config.Spec which means your kube generate code can just stay as it without changes.

[Luap99]

@umohnani8 I think if we merge #18721 then you do not need any code changes at all, you could just add your test to prevent future regressions.

[umohnani8]

@containers/podman-maintainers PTAL

[baude]

im taking comments from @Luap99 to indicate his LGTM

/lgtm