Fix startup boost workflow when limit is not set

[kamarabbas99]

What type of PR is this?

/kind bug

Fixes #
#8813 (comment)
Clarify the behaviour in the doc for what happens when limit is not specified in the pod resources or in the recommendation.

Does this PR introduce a user-facing change?

NONE

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

- [KEP]: (https://github.com/kubernetes/autoscaler/tree/master/vertical-pod-autoscaler/enhancements/7862-cpu-startup-boost#aep-7862-cpu-startup-boost)

[kamarabbas99]

/cc alextarasov-spot

[k8s-ci-robot]

@kamarabbas99: GitHub didn't allow me to assign the following users: alextarasov-spot.

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/assign alextarasov-spot

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[kamarabbas99]

If there are no more concerns, can I get approval on this to unblock #8813?

[adrianmoisey]

/lgtm

[omerap12]

/approve

[adrianmoisey]

/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: adrianmoisey, kamarabbas99, omerap12

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• vertical-pod-autoscaler/OWNERS [adrianmoisey,omerap12]
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