Upgrade base images

alpine ~> 3.12
python ~> 3.8

Author: amancevice

Dockerfile

@@ -1,5 +1,5 @@
-ARG ALPINE_VERSION=3.11
-ARG PYTHON_VERSION=3.7
+ARG ALPINE_VERSION=3.12
+ARG PYTHON_VERSION=3.8
 
 FROM python:${PYTHON_VERSION} AS lock
 WORKDIR /var/lib/pandas/
@@ -9,14 +9,13 @@ COPY Pipfile* /var/lib/pandas/
 RUN pipenv lock --requirements > requirements.txt
 RUN pipenv lock --requirements --dev > requirements-dev.txt
 
-FROM alpine:${ALPINE_VERSION} as alpine
+FROM python:${PYTHON_VERSION}-alpine as alpine
 WORKDIR /var/lib/pandas/
 COPY --from=lock /var/lib/pandas/ .
-RUN apk add --no-cache python3-dev libstdc++ && \
-    apk add --no-cache --virtual .build-deps g++ && \
+RUN apk add --no-cache --virtual .build-deps g++ && \
     ln -s /usr/include/locale.h /usr/include/xlocale.h && \
-    pip3 install $(grep numpy requirements.txt) && \
-    pip3 install -r requirements.txt && \
+    pip install $(grep numpy requirements.txt) && \
+    pip install -r requirements.txt && \
     apk del .build-deps
 
 FROM python:${PYTHON_VERSION}-slim AS slim