Migrate away from deprecated ioutil

[sebrandon1]

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

Go standard library modernization:

• Replaced usage of ioutil.ReadFile with os.ReadFile in support/thirdparty/kubernetes/pkg/credentialprovider/config.go to align with Go's standard library deprecations. [1] [2]
• Updated import from ioutil to io for stream discarding in pkg/etcdcli/etcdcli.go, and replaced ioutil.Discard with io.Discard in the gRPC logger configuration. [1] [2]

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

[coderabbitai]

Walkthrough

Two files are updated to migrate from the deprecated io/ioutil package to modern standard library equivalents: ioutil.Discard is replaced with io.Discard and ioutil.ReadFile is replaced with os.ReadFile.

Changes

Cohort / File(s)	Summary
Discard constant migration pkg/etcdcli/etcdcli.go	Replaced ioutil.Discard with io.Discard in grpclog.NewLoggerV2 call; updated import from io/ioutil to io.
ReadFile function migration support/thirdparty/kubernetes/pkg/credentialprovider/config.go	Replaced ioutil.ReadFile with os.ReadFile; updated import from io/ioutil to os. Function signature and error handling remain unchanged.

Estimated code review effort

🎯 1 (Trivial) | ⏱️ ~3 minutes

These are straightforward, homogeneous refactoring changes following a standard library deprecation pattern with no logic modifications or behavioral changes.

✨ Finishing touches

• 📝 Generate docstrings

🧪 Generate unit tests (beta)

• Create PR with unit tests
• Post copyable unit tests in a comment

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📥 Commits

Reviewing files that changed from the base of the PR and between 34cc9c7 and dcfbcf9.

📒 Files selected for processing (2)

• pkg/etcdcli/etcdcli.go (2 hunks)
• support/thirdparty/kubernetes/pkg/credentialprovider/config.go (2 hunks)

🧰 Additional context used

📓 Path-based instructions (1)

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⚙️ CodeRabbit configuration file

-Focus on major issues impacting performance, readability, maintainability and security. Avoid nitpicks and avoid verbosity.

Files:

• pkg/etcdcli/etcdcli.go
• support/thirdparty/kubernetes/pkg/credentialprovider/config.go

🧬 Code graph analysis (1)

support/thirdparty/kubernetes/pkg/credentialprovider/config.go (1)

karpenter-operator/controllers/karpenter/assets/assets.go (1)

• ReadFile (11-13)

🔇 Additional comments (2)

pkg/etcdcli/etcdcli.go (1)

6-6: LGTM! Correct migration from deprecated ioutil.

The import and usage changes correctly replace ioutil.Discard with io.Discard, aligning with Go 1.16+ deprecations.

Also applies to: 60-60

support/thirdparty/kubernetes/pkg/credentialprovider/config.go (1)

24-24: LGTM! Correct migration from deprecated ioutil.

The import and usage changes correctly replace ioutil.ReadFile with os.ReadFile, aligning with Go 1.16+ deprecations.

Also applies to: 52-52

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[openshift-ci]

[APPROVALNOTIFIER] This PR is NOT APPROVED

This pull-request has been approved by: sebrandon1
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[openshift-ci]

@sebrandon1: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
ci/prow/e2e-aks-4-20	dcfbcf9	link	true	/test e2e-aks-4-20
ci/prow/e2e-aks	dcfbcf9	link	true	/test e2e-aks
ci/prow/verify	dcfbcf9	link	true	/test verify

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[bryan-cox]

@sebrandon1 thanks for the PR! You'll need to include a body message with your commit per https://github.com/openshift/hypershift?tab=contributing-ov-file#readme for verify to pass.