update docker file with alpine 3.12 and small fix

Author: blankdots

Dockerfile

@@ -1,4 +1,4 @@
-FROM python:3.7-alpine3.9 as BACKEND
+FROM python:3.7-alpine3.12 as BACKEND
 
 RUN apk add --update \
     && apk add --no-cache build-base curl-dev linux-headers bash git\
@@ -13,15 +13,15 @@ RUN pip install --upgrade pip\
     && pip install -r /root/swift_upload_runner/requirements.txt \
     && pip install /root/swift_upload_runner
 
-FROM python:3.7-alpine3.9
+FROM python:3.7-alpine3.12
 
 RUN apk add --no-cache --update bash
 
 LABEL maintainer "CSC Developers"
 LABEL org.label-schema.schema-version="1.0"
 LABEL org.label-schema.vcs-url="https://github.com/CSCFI/swift-upload-runner"
 
-COPY --from=BACKEND usr/local/lib/python3.7 usr/local/lib/python3.7/
+COPY --from=BACKEND /usr/local/lib/python3.7 /usr/local/lib/python3.7/
 
 COPY --from=BACKEND /usr/local/bin/gunicorn /usr/local/bin/