MAPG-243 change base image of Dockerfile-test to the same as Dockerfile-app

docker/Dockerfile-test

@@ -1,4 +1,6 @@
-FROM php:7.4.7-cli-buster
+FROM ubuntu:focal
 
-RUN apt-get update && apt-get install -y unzip
+ENV DEBIAN_FRONTEND noninteractive
+
+RUN apt update && apt install -y curl git unzip php7.4-cli php7.4-mbstring php7.4-xml
 RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer