[docker: debian] reduce the image size dramatically! Compressed size from 240 MB~ to 100 MB~

docker/debian-base.dockerfile

@@ -4,8 +4,9 @@ FROM node:14-buster-slim
 WORKDIR /app
 
 # Install Apprise, add sqlite3 cli for debugging in the future, iputils-ping for ping, util-linux for setpriv
+# Stupid python3 and python3-pip actually install a lot of useless things into Debian, specific --no-install-recommends to skip them, make the base even smaller than alpine!
 RUN apt update && \
-    apt --yes install python3 python3-pip python3-cryptography python3-six python3-yaml python3-click python3-markdown python3-requests python3-requests-oauthlib \
+    apt --yes --no-install-recommends install python3 python3-pip python3-cryptography python3-six python3-yaml python3-click python3-markdown python3-requests python3-requests-oauthlib \
         sqlite3 iputils-ping util-linux dumb-init && \
     pip3 --no-cache-dir install apprise && \
     rm -rf /var/lib/apt/lists/*