dockerfile fix

@@ -6,9 +6,12 @@ RUN git clone http://gitlab.fjmaimaimai.com/mmm-go/gocomm.git /go/src/gocomm \
     && cd /go/src/gocomm \
     && cd /go/src/gocomm \
     && git pull
     && git pull
 WORKDIR /go/src/opp
 WORKDIR /go/src/opp
+
+COPY go.mod .
+RUN go mod download
+
 COPY . .
 COPY . .
-RUN go mod download \
-    && GOOS=linux CGO_ENABLED=0 go build -ldflags="-s -w"  -o opp main.go
+RUN GOOS=linux CGO_ENABLED=0 go build -ldflags="-s -w"  -o opp main.go
 
 
 FROM alpine:latest
 FROM alpine:latest
 RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.aliyun.com/g' /etc/apk/repositories \
 RUN sed -i 's/dl-cdn.alpinelinux.org/mirrors.aliyun.com/g' /etc/apk/repositories \