update to PHP 7.4

Dockerfile

@@ -1,17 +1,9 @@
-FROM php:7.3-fpm AS runtime
+FROM php:7.4-fpm AS runtime
 
 RUN set -ex \
  && apt-get update -y \
  && apt-get upgrade -y \
  && apt-get install -y libzip4 libzip-dev libpng-tools libpng16-16 libpng-dev libxml2-dev zlib1g-dev libldap2-dev \
- && curl -sS -o /tmp/icu.tar.gz -L http://download.icu-project.org/files/icu4c/62.1/icu4c-62_1-src.tgz \
- && tar -zxf /tmp/icu.tar.gz -C /tmp \
- && cd /tmp/icu/source \
- && ./configure --prefix=/usr/local \
- && make \
- && make install \
- && rm -rf /tmp/icu* \
- && docker-php-ext-configure intl --with-icu-dir=/usr/local \
  && docker-php-ext-install opcache pdo_mysql ldap zip xml gd intl \
 # clean up
  && apt-get purge -y --auto-remove -o APT::AutoRemove::RecommendsImportant=false -o APT::AutoRemove::SuggestsImportant=false \

composer.json

@@ -6,7 +6,7 @@
     "config": {
         "bin-dir": "bin",
         "platform": {
-            "php": "7.3"
+            "php": "7.4"
         },
         "sort-packages": true
     },