Subdivide pods orchestrator logic

[Duke0404]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Atomize the functionality of the scale up method of the pods scale up orchestrator so that they can be individually used in other parts of cluster autoscaler.

Which issue(s) this PR fixes:

Fixes #

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.:

cc: @aleksandra-malinowska @kawych

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Duke0404
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• cluster-autoscaler/OWNERS

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[k8s-ci-robot]

Hi @Duke0404. Thanks for your PR.

I'm waiting for a kubernetes member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

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