build: Build infrastructure images

Dockerfile.stupgrades

@@ -1,18 +1,8 @@
-ARG GOVERSION=latest
-FROM golang:$GOVERSION AS builder
-
-WORKDIR /src
-COPY . .
-
-ENV CGO_ENABLED=0
-ENV BUILD_HOST=syncthing.net
-ENV BUILD_USER=docker
-RUN rm -f stupgrades && go run build.go build stupgrades
-
 FROM alpine
+ARG TARGETARCH
 
 EXPOSE 8080
 
-COPY --from=builder /src/stupgrades /bin/stupgrades
+COPY stupgrades-linux-${TARGETARCH} /bin/stupgrades
 
 ENTRYPOINT [ "/bin/stupgrades" ]