Add support for controlling Users in IAM Groups

[naclonts]

Issue #, if available: aws-controllers-k8s/community#2207

Description of changes: Add support for a Users list under Group. The group's IAM users will be added or removed based on the list defined in the CR.

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

Testing

Added automated e2e tests.

Manual test

YAML file group_w_users.yaml :

apiVersion: iam.services.k8s.aws/v1alpha1
kind: Group
metadata:
  name: cool-peeps
spec:
  name: cool-peeps
  users:
    - nclonts

Apply:

% k apply -f group_w_users.yaml
group.iam.services.k8s.aws/cool-peeps configured

Verified AWS account has group cool-peeps that includes user nclonts.

[ack-prow]

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[ack-prow]

Hi @naclonts. Thanks for your PR.

I'm waiting for a aws-controllers-k8s member to verify that this patch is reasonable to test. If it is, they should reply with /ok-to-test on its own line. Until that is done, I will not automatically test new commits in this PR, but the usual testing commands by org members will still work. Regular contributors should join the org to skip this step.

Once the patch is verified, the new status will be reflected by the ok-to-test label.

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[knottnt]

Thinking about usability of this feature it might be better to add a list of groups to the User resource instead. A group can have hundreds to thousands of users in normal use, whereas a user would normally have a much more limited number number of groups.

[knottnt]

Could you add a description for the custom field? The CRD descriptions are used to generate our API reference docs. You should be able to do that in the generator.yaml with the DocumenationConfig.

[knottnt]

Could you pull the latest tags from upstream and rebuild.

[knottnt]

/hold