update endpointslice to enabled by default

[zac-nixon]

Issue

#4226

Description

Turns on EndPointSlices by default, as they are the de-facto way of working with Service Endpoints now.

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: zac-nixon

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[shraddhabang]

/lgtm
/approved

[shraddhabang]

Lets add a note for this in our release notes as well.

[k8s-ci-robot]

@zac-nixon: 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	55eaeae	link	true	/test pull-aws-load-balancer-controller-e2e-test

Full PR test history. Your PR dashboard. Please help us cut down on flakes by linking to an open issue when you hit one in your PR.

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