job controller: don't mutate shared cache object

[adtac]

What type of PR is this?

/kind bug

What this PR does / why we need it:

Cherry pick of 0a21157

Which issue(s) this PR fixes:

Fixes #100551

Special notes for your reviewer:

cc @ialidzhikov @alculquicondor @ahg-g

Does this PR introduce a user-facing change?

NONE

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

/sig apps

[adtac]

(Not using the cherry_pick_pull.sh script becase that PR has more than just the bug fix; you can't select specific commits with that shell script.)

[alculquicondor]

/lgtm

[ialidzhikov]

/assign @soltysh
for approval

[ialidzhikov]

ping @soltysh @ahg-g
for approval

[ahg-g]

@kubernetes/release-managers

[ialidzhikov]

@kubernetes/release-managers

@ahg-g , before tagging release managers, PR needs to be lgtm-ed and approve-ed by reviewers. Only after this release managers remove the do-not-merge/cherry-pick-not-approved label.

[ialidzhikov]

@ahg-g currently this PR is missing approved label :)

[ahg-g]

Right, only @soltysh can approve, but having it in the queue for release managers from now is good too.

[ahg-g]

/assign @janetkuo

since Maciek may not be available

[ialidzhikov]

/cc @kubernetes/release-managers

[cpanato]

/priority important-soon
/triage accepted

[cpanato]

/lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: adtac, cpanato, janetkuo

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Needs approval from an approver in each of these files:

• pkg/controller/job/OWNERS [janetkuo]

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