Fix docker build error

proxy/Dockerfile.amd64

@@ -0,0 +1,13 @@
+FROM amd64/debian:buster
+
+LABEL Lan Tian "lantian@lantian.pub"
+ENV GOOS=linux GOARCH=amd64
+WORKDIR /root
+COPY . .
+RUN apt-get -qq update && DEBIAN_FRONTEND=noninteractive apt-get -qq install -y golang traceroute \
+  && cd /root && go build -o /proxy \
+  && cd / && rm -rf /root/* \
+  && apt-get -qq purge -y golang \
+  && apt-get -qq autoremove --purge -y && apt-get clean && rm -rf /var/lib/apt/lists
+
+ENTRYPOINT ["/proxy"]