Add .spec.insecure to HelmRepository for type: oci

[stefanprodan]

Allow connecting to Helm OCI repositories over plain HTTP (non-TLS endpoint).

Example:

apiVersion: source.toolkit.fluxcd.io/v1beta2
kind: HelmRepository
metadata:
  name: podinfo
  namespace: default
spec:
  type: oci
  interval: 1h
  insecure: true
  url: oci://localhost:5000/charts

Closes: #957
Closes: fluxcd/helm-controller#782
Ref: helm/helm#12128

[makkes]

I think we should make this field name more explicit to (1) make it obvious what it does and (2) allow for any future "insecure" flags to be added.

Suggested change

	Insecure bool `json:"insecure,omitempty"`
	InsecurePlainHTTP bool `json:"insecure,omitempty"`

Insecure as a prefix still makes sense to me to make it obvious this is an insecure transport.

[stefanprodan]

This field matches what we have in OCIRepository and what's in the RFC.

[makkes]

That's unfortunate. I still believe it's a way better UX if it had a more telling name.

[makkes]

I pointed that out in the RFC PR, too, by the way: fluxcd/flux2#3081 (review)

[hiddeco]

The goal here at present is to get the feature in while continuing to be uniform. Dealing with the naming of the field would be a separate task, as aligning it across kinds would first require an amendment to the RFC.

[makkes]

I'm fine with merging this as my comment on the RFC PR also got completely ignored, anyway.

[aryan9600]

This PR is not ready to be merged, there are a lot of changes required for the new field to work properly. Thus, I have put this PR on hold for now.

[stefanprodan]

I've tested this PR in a real cluster with a local registry over HTTP and works great.