Opt-out the kustomize feature via go build tags

[yuwenma]

Problems:

• The k-d-p supports a kustomize hydration feature. This feature requires library kustomize/api. This library itself is commonly used by other libraries and users can encounter dependency conflicts if the other library uses a different kustomize/api release (what happened on my side and I cannot bump the other kustomize/api version).
• The k-d-p kustomize feature itself potentially causes friction issues, like fs operation, run kustomize before other transformation operations.

Description:

This PR split the kustomize hydration to 1. a generic kustomize build and 2. a no-op in different files; It adds a go build constraint without_kustomize to give users the ability to switch to opt out the kustomize feature in build time and no need to change their source code.

Test: This PR is tested using the guestbook example by changing the make run for the following two cases

1. Preserve existing feature

   make run

output

2023-01-27T23:29:57-08:00   INFO    running kustomize   {"controller": "guestbook-controller", "object": {"name":"guestbook-sample","namespace":"default"}, "namespace": "default", "name": "guestbook-sample", "reconcileID": "fbcb7051-36c0-4358-aafc-5c84c6b96e2a", "kustomizer": "EnabledKustomize"}

2. Skip kustomize

   # Makefile
   run: manifests generate fmt vet ## Run a controller from your host.
   go run -tags without_kustomize ./main.go

   make run

output

2023-01-27T23:38:37-08:00   INFO    skip running kustomize  {"controller": "guestbook-controller", "object": {"name":"guestbook-sample","namespace":"default"}, "namespace": "default", "name": "guestbook-sample", "reconcileID": "38da0981-8143-43e5-96a4-7e551018758f", "kustomizer": "SkipKustomize"}

UPDATED

go run -tags without_kustomize ./main.go

...
2023-01-28T23:16:16-08:00   ERROR   building deployment objects {"controller": "guestbook-controller", "object": {"name":"guestbook-sample","namespace":"default"}, "namespace": "default", "name": "guestbook-sample", "reconcileID": "b62ee9fb-be37-4094-9bb7-c3cce756c03e", "error": "error running kustomize: kustomize support is not compiled in (built with tag `without_kustomize`)"}

go run ./main.go

2023-01-28T23:19:46-08:00   INFO    running kustomize   {"controller": "guestbook-controller", "object": {"name":"guestbook-sample","namespace":"default"}, "namespace": "default", "name": "guestbook-sample", "reconcileID": "eb7c1f04-771e-45a1-b44f-d1b451357d46", "manifestPath": "channels/packages/guestbook/0.0.1"}

[yuwenma]

/assign @justinsb

[justinsb]

Thanks @yuwenma!

/approve /lgtm

[k8s-ci-robot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: justinsb, yuwenma

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[atoato88]

LGTM :smile: Should we add documentation about without_kustomize tag?

[yuwenma]

@atoato88 that's a good idea. I updated the doc here https://github.com/kubernetes-sigs/kubebuilder-declarative-pattern/pull/301 Please let me know if there's anywhere else I shall update.