fix(aws-cloudwatch-metrics): Add support for annotations

[jcastillocano]

Issue

Annotations are not supported, even if the documentation states so.

Description of changes

I'm adding support for annotations, and also fixing a typo in the doc.

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

Locally tested with helm template as follows:

1. Create defaults.yaml with the following content:

image:
  tag: 1.247349.0b251399
  pullPolicy: IfNotPresent

2. Run helm template against chart folder passing default.yaml as argument as follows: helm template aws-cloudwatch-metrics ~/git/eks-charts/stable/aws-cloudwatch-metrics --namespace amazon-cloudwatch --set clusterName=dev -f defaults.yaml
3. Verify we don't have any annotations in aws-cloudwatch-metrics/templates/daemonset.yaml resource.

# Source: aws-cloudwatch-metrics/templates/daemonset.yaml
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: aws-cloudwatch-metrics
  labels:
    helm.sh/chart: aws-cloudwatch-metrics-0.0.8
    app.kubernetes.io/name: aws-cloudwatch-metrics
    app.kubernetes.io/version: "1.247350"
    app.kubernetes.io/managed-by: Helm
spec:
  selector:
    matchLabels:
      app.kubernetes.io/name: aws-cloudwatch-metrics
  template:
    metadata:
      labels:
        app.kubernetes.io/name: aws-cloudwatch-metrics
    spec:

4. Amend the following lines to defaults.yaml

annotations:
  cluster-autoscaler.kubernetes.io/enable-ds-eviction: false
  cluster-autoscaler.kubernetes.io/safe-to-evict: false

5. Run helm template command from step 2, now we can see tolerations in both resource's metadata as well as template's metadata.

# Source: aws-cloudwatch-metrics/templates/daemonset.yaml
apiVersion: apps/v1
kind: DaemonSet
metadata:
  name: aws-cloudwatch-metrics
  labels:
    helm.sh/chart: aws-cloudwatch-metrics-0.0.8
    app.kubernetes.io/name: aws-cloudwatch-metrics
    app.kubernetes.io/version: "1.247350"
    app.kubernetes.io/managed-by: Helm
  annotations:
    cluster-autoscaler.kubernetes.io/enable-ds-eviction: false
    cluster-autoscaler.kubernetes.io/safe-to-evict: false
spec:
  selector:
    matchLabels:
      app.kubernetes.io/name: aws-cloudwatch-metrics
  template:
    metadata:
      labels:
        app.kubernetes.io/name: aws-cloudwatch-metrics
      annotations:
        cluster-autoscaler.kubernetes.io/enable-ds-eviction: false
        cluster-autoscaler.kubernetes.io/safe-to-evict: false
    spec:
...

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

[jcastillocano]

hi there! is there anything missing in this pr before it can be reviewed and merged? thx in advance!