Fix Karpenter addon not return null for instanceStorePolicy as default

[vumdao]

Issue #, if available:

7:34:19 PM | UPDATE_FAILED        | Custom::AWSCDK-EKS-KubernetesResource | selvcd1deveksbluep...detemplate2CEE3EE4
Received response status [FAILED] from custom resource. Message returned: Error: b'The EC2NodeClass "default-ec2nodeclass" is invalid: \n* spec.instanceStorePolicy: Unsupported value: "": supported values: "RAID0"\n* <
nil>: Invalid value: "null": some validation rules were not checked because the object was invalid; correct the existing errors to complete validation\n'

Logs: /aws/lambda/DeployDev-sel-vc-d1-dev-eks-bluepr-Handler886CB40B-h954A8KfTkdY

Description of changes:
Return null value for instanceStorePolicy as default value

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[youngjeong46]

Thanks for submitting the PR, this was missed on the last release.

LGTM!

[shapirov103]

Pending e2e. (Test account is in maintenance mode atm, ETA 1 day).

[shapirov103]

/do-e2e-tests

[aws-ia-ci]

end to end tests passed

[vumdao]

@shapirov103 When will we have a release/hotfix for this, my blueprint project is being failed without this.

[shapirov103]

@vumdao planning today or Monday.

[shapirov103]

1.14.1 is out.