Add --no-cache for apk in Dockerfile

This will prevent apk leaving cache in Docker image

Author: PeterDaveHello

Dockerfile

@@ -1,8 +1,8 @@
 FROM python:3.8-alpine
 
-RUN apk upgrade
+RUN apk upgrade --no-cache
 RUN apk add --no-cache rust cargo openssl-dev libffi-dev py3-pip python3 samba-client samba-common-tools yaml-dev
-RUN apk add --virtual build-dependencies build-base git \
+RUN apk add --no-cache --virtual build-dependencies build-base git \
   && git clone https://github.com/cddmp/enum4linux-ng.git \
   && pip install -r enum4linux-ng/requirements.txt \
   && apk del build-dependencies