Improve cross compilation according to latest operator SDK

Dockerfile

@@ -1,5 +1,7 @@
 # Build the manager binary
 FROM golang:1.19 as builder
+ARG TARGETOS
+ARG TARGETARCH
 
 WORKDIR /workspace
 # Copy the Go Modules manifests
@@ -15,11 +17,15 @@ COPY api/ api/
 COPY controllers/ controllers/
 
 # Build
-RUN CGO_ENABLED=0 GOOS=linux GOARCH=${TARGETARCH} GO111MODULE=on go build -a -o manager main.go
+# the GOARCH has not a default value to allow the binary be built according to the host where the command
+# was called. For example, if we call make docker-build in a local env which has the Apple Silicon M1 SO
+# the docker BUILDPLATFORM arg will be linux/arm64 when for Apple x86 it will be linux/amd64. Therefore,
+# by leaving it empty we can ensure that the container and binary shipped on it will have the same platform.
+RUN CGO_ENABLED=0 GOOS=${TARGETOS:-linux} GOARCH=${TARGETARCH} GO111MODULE=on go build -a -o manager main.go
 
 # Use distroless as minimal base image to package the manager binary
 # Refer to https://github.com/GoogleContainerTools/distroless for more details
-FROM gcr.io/distroless/static-debian11:nonroot
+FROM gcr.io/distroless/static:nonroot
 WORKDIR /
 COPY --from=builder /workspace/manager .
 USER 65532:65532

Makefile

@@ -139,7 +139,7 @@ PLATFORMS ?= linux/arm64,linux/amd64,linux/s390x,linux/ppc64le
 .PHONY: docker-buildx
 docker-buildx: test ## Build and push docker image for the manager for cross-platform support
 	# copy existing Dockerfile and insert --platform=${BUILDPLATFORM} into Dockerfile.cross, and preserve the original Dockerfile
-	sed -e 's/\(^FROM\)/FROM --platform=\$$\{BUILDPLATFORM\}/; t' -e '// s//FROM --platform=\$$\{BUILDPLATFORM\}/' Dockerfile > Dockerfile.cross
+	sed -e '1 s/\(^FROM\)/FROM --platform=\$$\{BUILDPLATFORM\}/; t' -e ' 1,// s//FROM --platform=\$$\{BUILDPLATFORM\}/' Dockerfile > Dockerfile.cross
 	- docker buildx create --driver-opt network=host --name project-v3-builder
 	docker buildx use project-v3-builder
 	- docker buildx build --push --platform=$(PLATFORMS) --tag ${IMG} -f Dockerfile.cross .