feat: use specified go version for docker build

Author: simonostendorf

Dockerfile

@@ -13,7 +13,8 @@
 # limitations under the License.
 
 # Build the manager binary
-FROM golang:1.23.0 AS builder
+ARG GO_VERSION
+FROM golang:${GO_VERSION} as builder
 WORKDIR /workspace
 
 # Run this with docker build --build_arg goproxy=$(go env GOPROXY) to override the goproxy

Makefile

@@ -330,7 +330,7 @@ generate-api-docs-%: $(GEN_CRD_API_REFERENCE_DOCS) FORCE
 
 .PHONY: docker-build
 docker-build: ## Build the docker image for controller-manager
-	docker build -f Dockerfile --build-arg goproxy=$(GOPROXY) --build-arg ARCH=$(ARCH) --build-arg ldflags="$(LDFLAGS)" . -t $(CONTROLLER_IMG_TAG)
+	docker build -f Dockerfile --build-arg GO_VERSION=$(GO_VERSION) --build-arg goproxy=$(GOPROXY) --build-arg ARCH=$(ARCH) --build-arg ldflags="$(LDFLAGS)" . -t $(CONTROLLER_IMG_TAG)
 
 .PHONY: docker-push
 docker-push: ## Push the docker image