testsys: Add support for node provisioning with Karpenter

[ecpullen]

Issue number:

Closes #N/A

Description of changes:

Enables the use of the agent created in bottlerocket-os/bottlerocket-test-system#803

Note: You can provision nodes with karpenter by specifying karpenter-block-device-mappings in Test.toml.
To follow the generic mapping, use the following configuration:

[aws-k8s.configuration.karpenter]
test-type = "quick"
karpenter-device-mapping = [
    {name = "/dev/xvda", volumeType = "gp3", volumeSize = 4, deleteOnTermination = true},
    {name = "/dev/xvdb", volumeType = "gp3", volumeSize = 20, deleteOnTermination = true},
]

This configuration creates a new test type for all aws-k8s variants called karpenter (the string following .configuration in the table heading).

Before launching nodes with karpenter you will need to add the karpenter role to your cluster's aws-auth config map.

# Change to your clusters name
CLUSTER_NAME=my-cluster
ACCOUNT_ID=your-account-id
REGION=us-west-2
eksctl create iamidentity mapping \
  -r ${REGION} \
  --cluster ${CLUSTER_NAME} \
  --arn arn:aws:iam::${ACCOUNT_ID}:role/KarpenterInstanceNodeRole \
  --username system:node:{{EC2PrivateDNSName}} \
  --group system:bootstrappers \
  --group system:nodes

You can run the test by calling,

cargo make -e TESTSYS_TEST=karpenter test

Testing done:

Verified that cargo make test still works as expected when sonobuoy-image is and is not provided.

Tested using the above instructions and verified that the instances we created and the test ran successfully.

Terms of contribution:

By submitting this pull request, I agree that this contribution is dual-licensed under the terms of both the Apache License, version 2.0, and the MIT license.

[ecpullen]

^ Small typo in documentation