[aws-cloudwatch-metrics] Add imagePullSecrets to the Helm Chart

[krlydm]

Issue

This is not an issue, it is an improvement.

Description of changes

Added imagePullSecrets to the daemonset to use if you need a secret to authenticate with a container repository.

Checklist

• Added/modified documentation as required (such as the README.md for modified charts)
• Incremented the chart version in Chart.yaml for the modified chart(s)
• Manually tested. Describe what testing was done in the testing section below
• Make sure the title of the PR is a good description that can go into the release notes

Testing

This change was deployed to an EKS cluster using the chart locally.

By submitting this pull request, I confirm that my contribution is made under the terms of the Apache 2.0 license.

[krlydm]

@bwagner5 @kishorj Let me know if you need anything else for this.

[krlydm]

@bwagner5 @kishorj Apologize for pinging you on this again, but it would be great if we can somehow make progress on this request. Solving this is important for us to be able to access the docker images through our private docker registry which is configured to cache images from the dockerhub.

[krlydm]

@bwagner5 @kishorj Let me know if you need anything else on this.