updated IAM policy for lb2 service account

[jjames3]

What does this PR do?

Adds missing permission to IAM role assume by AWS Load Balancer Controller pods.

Motivation

While deploying example at "examples/ipv6-eks-cluster" an EKS cluster along with addon alb-ingress-controller is created. However when I tried to create an Ingress, alb-ingress-controller pod was failing to add targets to TargetGroup with AccessDenied error on permission "ec2:DescribeVpcPeeringConnections". Thus this PR includes commit on missing permission "ec2:DescribeVpcPeeringConnections".

More

• Yes, I have tested the PR using my local account setup (Provide any test evidence report under Additional Notes)
• Yes, I have added a new example under examples to support my PR
• Yes, I have created another PR for add-ons under add-ons repo (if applicable)
• Yes, I have updated the docs for this feature
• Yes, I ran pre-commit run -a with this PR

Note: Not all the PRs required examples and docs except a new pattern or add-on added.

For Moderators

• E2E Test successfully complete before merge?

Additional Notes

[vara-bonthu]

Thanks for the fix @jjames3