Revert "packaging: update Dockerfile (#2563)" (#2564)

This reverts commit 392dc7e.

Signed-off-by: Alexander Yastrebov <alexander.yastrebov@zalando.de>

packaging/Dockerfile

@@ -1,20 +1,16 @@
 ARG BASE_IMAGE=default
-ARG BUILD_FOLDER=build
-ARG TARGETPLATFORM
-
 FROM registry.opensource.zalan.do/library/alpine-3:latest AS default
 FROM ${BASE_IMAGE}
 LABEL maintainer="Team Gateway&Proxy @ Zalando SE <team-gwproxy@zalando.de>"
-
-RUN cat /etc/alpine-release \
-    && apk --no-cache add ca-certificates \
-    && update-ca-certificates
-
-COPY ${BUILD_FOLDER}/${TARGETPLATFORM}/skipper \
+RUN apk --no-cache add ca-certificates && update-ca-certificates
+RUN mkdir -p /usr/bin
+ARG BUILD_FOLDER=build
+ARG TARGETPLATFORM
+ADD ${BUILD_FOLDER}/${TARGETPLATFORM}/skipper \
     ${BUILD_FOLDER}/${TARGETPLATFORM}/eskip \
     ${BUILD_FOLDER}/${TARGETPLATFORM}/webhook \
-    ${BUILD_FOLDER}/${TARGETPLATFORM}/routesrv \
-    /usr/bin/
+    ${BUILD_FOLDER}/${TARGETPLATFORM}/routesrv /usr/bin/
+ENV PATH $PATH:/usr/bin
 
 EXPOSE 9090 9911