reduce image size

Dockerfile

@@ -4,6 +4,7 @@ RUN apk add gcc g++ libc-dev
 WORKDIR /go/src/github.com/mayswind/lab
 COPY . .
 RUN GOOS=linux GOARCH=amd64 CGO_ENABLED=1 go build -a -v -i -trimpath -o lab lab.go
+RUN chmod +x lab
 
 # Build frontend files
 FROM node:12.19.0-alpine3.12 AS fe-builder
@@ -17,7 +18,6 @@ FROM alpine:3.12.0
 RUN addgroup -S -g 1000 labapp && adduser -S -G labapp -u 1000 labapp
 RUN apk --no-cache add su-exec tzdata
 COPY --from=be-builder /go/src/github.com/mayswind/lab/lab /usr/local/bin/labapp/lab
-RUN chmod +x /usr/local/bin/labapp/lab
 COPY --from=fe-builder /go/src/github.com/mayswind/lab/dist /usr/local/bin/labapp/public
 COPY conf /usr/local/bin/labapp/conf
 WORKDIR /usr/local/bin/labapp