Use scratch as the base image for operator (open-telemetry#2014)

.chloggen/chore_dockerfile-base-scratch.yaml

@@ -0,0 +1,16 @@
+# One of 'breaking', 'deprecation', 'new_component', 'enhancement', 'bug_fix'
+change_type: enhancement
+
+# The name of the component, or a single word describing the area of concern, (e.g. operator, target allocator, github action)
+component: operator
+
+# A brief description of the change. Surround your text with quotes ("") if it needs to start with a backtick (`).
+note: Use scratch as the base image for operator
+
+# One or more tracking issues related to the change
+issues: [2011]
+
+# (Optional) One or more lines of additional information to render under the primary note.
+# These lines will be padded with 2 spaces and then inserted directly into the document.
+# Use pipe (|) for multiline entries.
+subtext:

Dockerfile

@@ -1,7 +1,10 @@
 # Build the manager binary
-FROM golang:1.21 as builder
+FROM golang:1.21-alpine as builder
 
 WORKDIR /workspace
+
+RUN apk --no-cache add ca-certificates
+
 # Copy the Go Modules manifests
 COPY go.mod go.mod
 COPY go.sum go.sum
@@ -33,10 +36,14 @@ ARG AUTO_INSTRUMENTATION_GO_VERSION
 # Build
 RUN CGO_ENABLED=0 GOOS=linux GO111MODULE=on go build -ldflags="-X ${VERSION_PKG}.version=${VERSION} -X ${VERSION_PKG}.buildDate=${VERSION_DATE} -X ${VERSION_PKG}.otelCol=${OTELCOL_VERSION} -X ${VERSION_PKG}.targetAllocator=${TARGETALLOCATOR_VERSION} -X ${VERSION_PKG}.operatorOpAMPBridge=${OPERATOR_OPAMP_BRIDGE_VERSION} -X ${VERSION_PKG}.autoInstrumentationJava=${AUTO_INSTRUMENTATION_JAVA_VERSION} -X ${VERSION_PKG}.autoInstrumentationNodeJS=${AUTO_INSTRUMENTATION_NODEJS_VERSION} -X ${VERSION_PKG}.autoInstrumentationPython=${AUTO_INSTRUMENTATION_PYTHON_VERSION} -X ${VERSION_PKG}.autoInstrumentationDotNet=${AUTO_INSTRUMENTATION_DOTNET_VERSION} -X ${VERSION_PKG}.autoInstrumentationGo=${AUTO_INSTRUMENTATION_GO_VERSION} -X ${VERSION_PKG}.autoInstrumentationApacheHttpd=${AUTO_INSTRUMENTATION_APACHE_HTTPD_VERSION}" -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:nonroot
+######## Start a new stage from scratch #######
+FROM scratch
+
 WORKDIR /
+
+# Copy the certs from the builder
+COPY --from=builder /etc/ssl/certs/ca-certificates.crt /etc/ssl/certs/ca-certificates.crt
+
 COPY --from=builder /workspace/manager .
 USER 65532:65532