CLean unused files + add default squid.conf

Dockerfile

@@ -100,7 +100,7 @@ RUN echo "deb-src http://deb.debian.org/debian buster main contrib" >> /etc/apt/
     && cp src/squid /usr/sbin/ \
     && cp tools/squidclient/squidclient /usr/sbin/ \
     && cp src/mime.conf.default /etc/squid/mime.conf \
-    && cp src/squid.conf /etc/squid/ \
+    && cp src/squid.conf.default /etc/squid/squid.conf \
     && chown -Rf squid /etc/squid \
     && chown -Rf squid /usr/lib/squid \
     && chown -Rf squid /var/log/squid \