🐛 fix inmemory provider docker build

Makefile

@@ -734,7 +734,7 @@ docker-build-docker-infrastructure: ## Build the docker image for docker infrast
 
 .PHONY: docker-build-in-memory-infrastructure
 docker-build-in-memory-infrastructure: ## Build the docker image for in-memory infrastructure controller manager
-	cd $(CAPIM_DIR); DOCKER_BUILDKIT=1 docker build --build-arg builder_image=$(GO_CONTAINER_IMAGE) --build-arg goproxy=$(GOPROXY) --build-arg ARCH=$(ARCH) --build-arg ldflags="$(LDFLAGS)" ../../.. -t $(CAPIM_CONTROLLER_IMG)-$(ARCH):$(TAG) --file ../../../Dockerfile
+	cd $(CAPIM_DIR); DOCKER_BUILDKIT=1 docker build --build-arg builder_image=$(GO_CONTAINER_IMAGE) --build-arg goproxy=$(GOPROXY) --build-arg ARCH=$(ARCH) --build-arg ldflags="$(LDFLAGS)" ../../.. -t $(CAPIM_CONTROLLER_IMG)-$(ARCH):$(TAG) --file Dockerfile
 	$(MAKE) set-manifest-image MANIFEST_IMG=$(CAPIM_CONTROLLER_IMG)-$(ARCH) MANIFEST_TAG=$(TAG) TARGET_RESOURCE="$(CAPIM_DIR)/config/default/manager_image_patch.yaml"
 	$(MAKE) set-manifest-pull-policy TARGET_RESOURCE="$(CAPIM_DIR)/config/default/manager_pull_policy.yaml"
 

test/infrastructure/inmemory/Dockerfile

@@ -0,0 +1,80 @@
+# syntax=docker/dockerfile:1.4
+
+# Copyright 2023 The Kubernetes Authors.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+# Build the manager binary
+# Run this with docker build --build-arg builder_image=<golang:x.y.z>
+ARG builder_image
+
+# Build architecture
+ARG ARCH
+
+# Ignore Hadolint rule "Always tag the version of an image explicitly."
+# It's an invalid finding since the image is explicitly set in the Makefile.
+# https://github.com/hadolint/hadolint/wiki/DL3006
+# hadolint ignore=DL3006
+FROM ${builder_image} as builder
+WORKDIR /workspace
+
+# Run this with docker build --build-arg goproxy=$(go env GOPROXY) to override the goproxy
+ARG goproxy=https://proxy.golang.org
+ENV GOPROXY=$goproxy
+
+# Copy the Go Modules manifests
+COPY go.mod go.mod
+COPY go.sum go.sum
+
+# Essentially, change directories into the test go module
+WORKDIR /workspace/test
+# Copy the Go Modules manifests
+COPY test/go.mod go.mod
+COPY test/go.sum go.sum
+
+# Cache deps before building and copying source so that we don't need to re-download as much
+# and so that source changes don't invalidate our downloaded layer
+RUN --mount=type=cache,target=/go/pkg/mod \
+    go mod download
+
+# This needs to build with the entire Cluster API context
+WORKDIR /workspace
+# Copy the sources (which includes the test/infrastructure/inmemory subdirectory)
+COPY ./ ./
+
+# Essentially, change directories into CAPIM
+WORKDIR /workspace/test/infrastructure/inmemory
+
+# Cache the go build into the Go’s compiler cache folder so we take benefits of compiler caching across docker build calls
+RUN --mount=type=cache,target=/root/.cache/go-build \
+    --mount=type=cache,target=/go/pkg/mod \
+    go build .
+
+# Build
+ARG ARCH
+ARG ldflags
+
+# Do not force rebuild of up-to-date packages (do not use -a) and use the compiler cache folder
+RUN --mount=type=cache,target=/root/.cache/go-build \
+    --mount=type=cache,target=/go/pkg/mod \
+    CGO_ENABLED=0 GOOS=linux GOARCH=${ARCH} \
+    go build -trimpath -ldflags "${ldflags} -extldflags '-static'" \
+    -o /workspace/manager .
+
+
+FROM gcr.io/distroless/static:nonroot-${ARCH}
+WORKDIR /
+COPY --from=builder /workspace/manager .
+# Use uid of nonroot user (65532) because kubernetes expects numeric user when applying pod security policies
+USER 65532
+ENTRYPOINT ["/manager"]