Improve the building steps and add a target for new CRDs

[manuelbuil]

This PR does several things:

1 - Adds a way to easily generate new CRDs if we change some of the fields in pkg/apis/helm.cattle.io/types.go: it adds a new target in the Makefile (generate-crd) that is considered as a dependency of the build target. It also adds a new target in the Dockerfile which copies over the new crds

2 - Related to 1, this PR moves the installation of controller-gen to the builder stage because this is where it makes sense to have the new CRDs, as we need them to build helm-controller here

3 - Adds go generate in the builder stage and also installs crd-ref-docs because we need it as part of the code generation here. I picked github.com/elastic because that seems to be the best project right now to get crd-ref-docs as apposed to "ahmetb/gen-crd-api-reference-docs" that is unmaintained

4 - Removes "goimports@gopls" installation. We are executing go fmt and golangci-lint in the validation step but no goimports

5 - Adds manifests/crd.yaml because we are talking about it in the README and improves the README a bit because it was slightly outdated

6 - Updates controller-gen to v0.19.0

7 - Removes gcc and musl-dev from the dev stage as the build is happening in the builder stage

[brandond]

Suggested change

	Run `make build` to build the binary and, opitonally, generate new CRDs if the API changed. We recommend execute `make` to additionally run validation and testing.
	Run `make build` to build the binary and, optionally, generate new CRDs if the API changed. We recommend just running `make`, as the default target will also perform validation and testing.

[manuelbuil]

thanks

[brandond]

Why are we checking in a SECOND copy of the CRDs? They are already here: https://github.com/k3s-io/helm-controller/tree/master/pkg/crds/yaml/generated

See also the mechanism that we are using for k3s-io/api, rancher/helm-controller, and rancher/rancher:

• https://github.com/k3s-io/api/tree/main/pkg/crds/yaml/generated
• https://github.com/k3s-io/helm-controller/tree/master/pkg/crds/yaml/generated
• https://github.com/rancher/rancher/tree/main/pkg/crds/yaml/generated

[manuelbuil]

I added it Just because the README talks about ./manifests/crd.yaml. But now thinking about this, it's better if we change the README

[brandond]

I picked github.com/elastic because that seems to be the best project right now to get crd-ref-docs as apposed to "ahmetb/gen-crd-api-reference-docs" that is unmaintained

That is exactly what I used to generate the existing docs pages - did I forget to check that in?

See for example what I added to system-upgrade controller: rancher/system-upgrade-controller@42e0dc3

[brandond]

oh no I did add that to go generate:

helm-controller/main.go

Line 5 in 00cae7b

//go:generate crd-ref-docs --config=crd-ref-docs.yaml --renderer=markdown --output-path=doc/helmchart.md

I just didn't add it to the Dockerfile.