fix: drop remove node label and fix decrease size func

[nickstern2002]

What type of PR is this?

What this PR does / why we need it:

Two changes present in this PR

Dropping logic that adds the remove-node label

• The ToBeDeletedByClusterAutoscaler taint will be used as an indicator that a node should be removed from the node group. The remove-node label will only be managed by an internal controller
• The Autoscaler's usage of the remove-node label was causing conflicts with the internal controller responsible for reconciling node groups.

Taking the absolute value of delta in the DecreaseTargetSize

• This is fixing a bug in the current CoreWeave Autoscaler implementation. When DecreaseTargetSize is called delta is passed as a negative value. The CW Autoscaler currently assumes delta is positive. Taking the absolute value of delta resolves this difference

Which issue(s) this PR fixes:

Fixes #

Special notes for your reviewer:

Does this PR introduce a user-facing change?

This improves the user experience when using the CoreWeave implementation of the Cluster Autoscaler. Specifically prevents scenarios such as too many nodes getting removed and node groups being mistakenly scaled up. 

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

[linux-foundation-easycla]

The committers listed above are authorized under a signed CLA.

• ✅ login: nickstern2002 / name: Nick Sternheim (6d42554)

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[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: nickstern2002
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