fix: pod errors when nodepool requirements filter all instance types

[rschalo]

Fixes #N/A

Description
When NodeClaimTemplates are generated for the scheduling code, if NodePool requirements filter out all instance types then zero NodeClaimTemplates will be used for the parallelizeUntil call in the scheduler code. It's still important for Karpenter to ack the pods if the pods can schedule to existing or in-flight capacity, so after those checks if zero NodeClaimTemplates exist, a default error is sent back for the pod via podErrors.

How was this change tested?
Expanded unit testing and make presubmit

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[coveralls]

Pull Request Test Coverage Report for Build 16059149055

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 11 of 11 (100.0%) changed or added relevant lines in 2 files are covered.
• 32 unchanged lines in 4 files lost coverage.
• Overall coverage increased (+0.002%) to 81.876%

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Files with Coverage Reduction	New Missed Lines	%
pkg/test/cachesyncingclient.go	2	84.38%
pkg/controllers/node/termination/controller.go	3	77.37%
pkg/controllers/provisioning/scheduling/nodeclaim.go	3	89.66%
pkg/controllers/disruption/queue.go	24	77.83%

Totals
Change from base Build 15989448170:	0.002%
Covered Lines:	10219
Relevant Lines:	12481

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💛 - Coveralls