fix: unnecessary HPA updates when cpu utilization trigger is used

[uucloud]

To address the issue of continuous updates triggered by discrepancies between the ScaledObject and Kubernetes HPA v2 when using CPU utilization triggers, I have implemented a logic similar to the conversion logic used for HPA v1.

This change ensures that the handling of CPU utilization triggers is consistent and prevents the KEDA operator from continuously detecting differences and updating the HPA. The solution mimics the behavior observed when converting HPA v1, thus maintaining stability and expected behavior within the system.

However, this change may cause discrepancies in the latest version (Kubernetes version >= 1.27) of ScaledObject compared to user expectations. Specifically, when users configure CPU utilization triggers, the generated HPA places the CPU utilization metric last. If multiple CPU utilization triggers are configured, only the first one will take effect.

Checklist

• When introducing a new scaler, I agree with the scaling governance policy
• I have verified that my change is according to the deprecations & breaking changes policy
• Tests have been added
• Changelog has been updated and is aligned with our changelog requirements
• A PR is opened to update our Helm chart (repo) (if applicable, ie. when deployment manifests are modified)
• A PR is opened to update the documentation on (repo) (if applicable)
• Commits are signed with Developer Certificate of Origin (DCO - learn more)

Fixes #5821

[zroubalik]

Does the same applies to memory scaler? Do you think we can add some unit test? Also, could you please add changelog entry? (Improvements section)

Thanks for the contribution!

[uucloud]

Does the same applies to memory scaler?

Memory scaler will not have its order altered because HPA v1 only supports CPU utilization. Only CPU utilization metrics are stored separately, causing the order discrepancy.

Do you think we can add some unit test?

I have added the unit tests as requested.

could you please add changelog entry?

Sure, I will add the changelog entry.

[stale]

This issue has been automatically marked as stale because it has not had recent activity. It will be closed in 7 days if no further activity occurs. Thank you for your contributions.