Fix compose install in Dockerfile

Use official docker/compose alpine image as base
Fixes exoframejs/exoframe#226

Author: yamalight

Dockerfile

@@ -1,7 +1,7 @@
-FROM alpine
+FROM docker/compose:1.24.0
 
-# install required libs, docker-compose and yarn
-RUN apk update && apk add --no-cache libstdc++ libgcc py-pip yarn && pip install docker-compose
+# install required libs and yarn
+RUN apk update && apk add --no-cache libstdc++ libgcc yarn
 
 # copy binary
 COPY exoframe-server /