Add pods sharding processor that allows sharding on user specified node selectors

[Duke0404]

What type of PR is this?

/kind feature

What this PR does / why we need it:

Adds pod sharding pod list processor and its component processors which can be used to shard and filter pods for processing during current autoscaling iteration, based on user specified node selectors and for further optimizations.

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

Enables processing of pods with specific node selelctors in a separate autoscaling loop based using pod sharding.

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

cc: @aleksandra-malinowska @kawych @yaroslava-serdiuk

[k8s-ci-robot]

Hi @Duke0404. Thanks for your PR.

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[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: Duke0404
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[k8s-ci-robot]

PR needs rebase.

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[k8s-triage-robot]

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/lifecycle stale

[k8s-triage-robot]

The Kubernetes project currently lacks enough active contributors to adequately respond to all PRs.

This bot triages PRs according to the following rules:

• After 90d of inactivity, lifecycle/stale is applied
• After 30d of inactivity since lifecycle/stale was applied, lifecycle/rotten is applied
• After 30d of inactivity since lifecycle/rotten was applied, the PR is closed

You can:

• Mark this PR as fresh with /remove-lifecycle rotten
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• Offer to help out with Issue Triage

Please send feedback to sig-contributor-experience at kubernetes/community.

/lifecycle rotten