Dockerfile corrected. Build failures

Dockerfile

@@ -5,13 +5,16 @@ WORKDIR ui
 RUN npm install && ng build --prod
 
 
-FROM golang:1.17.5 AS GO_BUILD
+FROM golang:alpine AS GO_BUILD
 COPY ./ /server
 WORKDIR /server
+ADD go.mod .
+ADd go.sum .
+RUN go mod download
 RUN go build -o /go/bin/server
 
 FROM alpine:3.15
 WORKDIR app
 COPY --from=ANGULAR_BUILD /ui/dist/ui/* ./ui/dist/ui/
 COPY --from=GO_BUILD /go/bin/server ./
-CMD /app/server
+CMD ./server