Fix weighted target group comparison for forward action

[shraddhabang]

Issue

LBC was incorrectly handling listener rules with weighted target groups, causing unnecessary rule modifications and creations instead of efficient priority reordering.

Description

The CompareOptionForTargetGroupTuples function was not sorting target groups by ARN, causing equivalent configurations with different orders to be considered different. This led to:

• Unnecessary ModifyRule/CreateRule API calls instead of SetRulePriorities
• Temporary rule deletions causing 4XX errors during updates

Fix:

1. Add ARN-based sorting in target group comparison transformer
2. Maintained backward compatibility for single target group scenarios
3. Added Comprehensive unit tests for complex scenarios

Local Testing Verification

Using an ingress with two rules having weighted target group actions:

Before Fix:

• Changing priority of weighted target group rules → 2 ModifyRule API calls

After Fix:

• Changing priority of weighted target group rules → 1 SetRulePriorities API call

Checklist

• Added tests that cover your change (if possible)
• Added/modified documentation as required (such as the README.md, or the docs directory)
• Manually tested
• Made sure the title of the PR is a good description that can go into the release notes

BONUS POINTS checklist: complete for good vibes and maybe prizes?! 🤯

• Backfilled missing tests for code in same general area 🎉
• Refactored something and made the world a better place 🌟

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: shraddhabang

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• OWNERS [shraddhabang]

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[zac-nixon]

/approved
/lgtm

[k8s-ci-robot]

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

Test name	Commit	Details	Required	Rerun command
pull-aws-load-balancer-controller-e2e-test	7f7c5da	link	true	/test pull-aws-load-balancer-controller-e2e-test

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