Docker: Ubuntu 20.04 (#2925)

https://ubuntu.com/blog/ubuntu-20-04-lts-arrives
PHP 7.4.3, Apache 2.4.41
https://php.net/migration74
We have already addressed PHP 7.4 issues in FreshRSS 1.16

Docker/Dockerfile

@@ -1,4 +1,4 @@
-FROM ubuntu:19.10
+FROM ubuntu:20.04
 
 ENV TZ UTC
 SHELL ["/bin/bash", "-o", "pipefail", "-c"]

Docker/Dockerfile-QEMU-ARM

@@ -1,7 +1,7 @@
 # Only relevant for Docker Hub or QEMU multi-architecture builds.
 # Prefer the normal `Dockerfile` if you are building manually on the targeted architecture.
 
-FROM arm32v7/ubuntu:19.10
+FROM arm32v7/ubuntu:20.04
 
 # Requires ./hooks/*
 COPY ./Docker/qemu-arm-* /usr/bin/