🌱 Move /exp/controllers to internal

[shivanshuraj1333]

What this PR does / why we need it:
Move /exp/controllers to internal and create alias.go for exposing Reconciler

Which issue(s) this PR fixes (optional, in fixes #<issue number>(, fixes #<issue_number>, ...) format, will close the issue(s) when PR gets merged):
Ref: #5455

[sbueringer]

Hey @shivanshu1333,
thx for opening this PR! Some tips on how to resolve the open issues:

• golangci-lint: You can either run make lint-fix (which rungs golangci-lint with the -fix flag) or goimports and gofmt manually
• verify-main: You have to add: paths=./$(EXP_DIR)/internal/... \ after paths=./$(EXP_DIR)/controllers/... \ in our top-level Makefile

Otherwise the PR looks great!

[shivanshuraj1333]

Thank you! I've updated the PR :)

[fabriziopandini]

@shivanshu1333 thanks! PR looks great

Could you kindly add this PR to the list under API change documentation for provider implementers

[sbueringer]

@shivanshu1333 thanks! PR looks great

Could you kindly add this PR to the list under API change documentation for provider implementers

+1 and please with the /controllers suffix (as that's the package we're actually moving), cf. https://github.com/kubernetes-sigs/cluster-api/pull/5647/files

[killianmuldoon]

/retest

[sbueringer]

Thx!, last nit from my side

[fabriziopandini]

lgtm pending addressing latest comments

[sbueringer]

@shivanshu1333 Thx, looks great!

/lgtm

[shivanshuraj1333]

/retest

[k8s-ci-robot]

@shivanshu1333: 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-cluster-api-apidiff-main	1c93435	link	false	/test pull-cluster-api-apidiff-main

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.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository. I understand the commands that are listed here.

[sbueringer]

/lgtm

You can ignore the apidiff. The markdown link check can (by us) afaik only be retrigger by another commit -amend + push -force. I'm not sure if it blocks the merge. PR status seems to suggest it doesn't https://prow.k8s.io/pr?query=is%3Apr+repo%3Akubernetes-sigs%2Fcluster-api+author%3Ashivanshu1333+head%3Acleanup%2Fmain%2F5455

[sbueringer]

/assign @fabriziopandini

[sbueringer]

@fabriziopandini If you have some time, this PR should be ready for merge now.

[fabriziopandini]

/lgtm
/approve

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: fabriziopandini

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