[WIP] refactor default config handling

[ElvinEfendi]

What this PR does / why we need it:
ignore this for now

Which issue this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close that issue when PR gets merged): fixes #

Special notes for your reviewer:

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[ElvinEfendi]

/remove-lifecycle stale

[k8s-ci-robot]

@ElvinEfendi: The following tests failed, say /retest to rerun them all:

Test name	Commit	Details	Rerun command
pull-ingress-nginx-e2e-1-15	8e7ea71	link	/test pull-ingress-nginx-e2e-1-15
pull-ingress-nginx-lualint	8e7ea71	link	/test pull-ingress-nginx-lualint

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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