Migrate away from deprecated ioutil

[sebrandon1]

ioutil has been deprecated since Go 1.16: https://go.dev/doc/go1.16#ioutil

Tracking issue: redhat-best-practices-for-k8s/telco-bot#52

Migration from ioutil to io/os:

• Replaced ioutil.ReadAll with io.ReadAll in imagepolicy.go and imagepolicy_test.go for reading configuration data from readers. [1] [2] [3]
• Replaced ioutil.WriteFile with os.WriteFile in audit.go for writing audit policy files.

Cleanup of deprecated imports:

• Removed all ioutil import statements from imagepolicy.go, imagepolicy_test.go, and audit.go. [1] [2] [3]

[ibihim]

/lgtm

[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: ibihim, sebrandon1
Once this PR has been reviewed and has the lgtm label, please assign deads2k for approval. For more information see the Code Review Process.

The full list of commands accepted by this bot can be found here.

Details

Needs approval from an approver in each of these files:

• OWNERS

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[openshift-ci]

New changes are detected. LGTM label has been removed.

[sebrandon1]

/retest

[openshift-ci]

@sebrandon1: all tests passed!

Full PR test history. Your PR dashboard.

Details

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes-sigs/prow repository. I understand the commands that are listed here.