Make sure to treat notices as errors to match GitHub actions and server

Author: lucwollants

docker/php7.4/Dockerfile

@@ -5,6 +5,8 @@ RUN apt-get update && apt-get install -y \
     git \
     && rm -rf /var/lib/apt/lists/*
 
+RUN echo "error_reporting = E_ALL & ~E_DEPRECATED & ~E_STRICT" > $PHP_INI_DIR/conf.d/error_reporting.ini
+
 RUN curl -sS https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
 WORKDIR /cdb