use remote sia dockerfile

docker-compose.yml

@@ -16,8 +16,8 @@ networks:
 services:
   sia:
     build:
-      context: ./docker/sia
-      dockerfile: Dockerfile
+      context: https://github.com/SkynetLabs/docker-skyd.git#main
+      dockerfile: scratch/Dockerfile
       args:
         branch: portal-latest
     container_name: sia

docker/sia/Dockerfile

@@ -1,16 +0,0 @@
-FROM golang:1.16.7 AS sia-builder
-
-ENV GOOS linux
-ENV GOARCH amd64
-
-ARG branch=portal-latest
-
-RUN git clone https://gitlab.com/SkynetLabs/skyd.git Sia --single-branch --branch ${branch} && \
-    make release --directory Sia
-
-FROM nebulouslabs/sia:1.5.6
-
-COPY --from=sia-builder /go/bin/ /usr/bin/
-
-RUN if [ -f "/usr/bin/skyd" ]; then mv /usr/bin/skyd /usr/bin/siad; fi && \
-    if [ -f "/usr/bin/skyc" ]; then mv /usr/bin/skyc /usr/bin/siac; fi