Proposed change to in-build docker-compose.yml and Dockerfile. The current implementation uses php 7.4, which is no longer compatible with the required PHP version of the server. I upped this to PHP 8.1

List of changes:
- Upped PHP Version to 8.1
- Added Apache Webserver so the Container works "out of the box" after docker-compose up -d
- Mounting whole project as volume to /var/www/html in docker-compose.yml (and set WORKDIR to /var/www/html)

Tested in a Docker for Windows environment.

.devcontainer/Dockerfile

 
 # PHP
 RUN apt-get update -y
+
+RUN apt install -y apache2 vim software-properties-common
+
+RUN add-apt-repository ppa:ondrej/php
+
 RUN apt-get install --no-install-recommends -y \
-    php7.4 \
-    php7.4-gd \
-    php7.4-zip \
-    php7.4-curl \
-    php7.4-xml \
-    php7.4-mbstring \
-    php7.4-sqlite \
-    php7.4-xdebug \
-    php7.4-pgsql \
-    php7.4-intl \
-    php7.4-imagick \
-    php7.4-gmp \
-    php7.4-apcu \
-    php7.4-bcmath \
+    php8.1 \
+    php8.1-common \
+    php8.1-gd \
+    php8.1-zip \
+    php8.1-curl \
+    php8.1-xml \
+    php8.1-xmlrpc \
+    php8.1-mbstring \
+    php8.1-sqlite \
+    php8.1-xdebug \
+    php8.1-pgsql \
+    php8.1-intl \
+    php8.1-imagick \
+    php8.1-gmp \
+    php8.1-apcu \
+    php8.1-bcmath \
+    php8.1-redis \
+    php8.1-soap \
+    php8.1-imap \
+    php8.1-opcache \
+    php8.1-cli \
+    php8.1-dev \
     libmagickcore-6.q16-3-extra \
     curl \
-    vim \
     lsof \
     make \
     nodejs \
     npm
 
-RUN echo "xdebug.remote_enable = 1" >> /etc/php/7.4/cli/conf.d/20-xdebug.ini
-RUN echo "xdebug.remote_autostart = 1" >> /etc/php/7.4/cli/conf.d/20-xdebug.ini
+RUN echo "xdebug.remote_enable = 1" >> /etc/php/8.1/cli/conf.d/20-xdebug.ini
+RUN echo "xdebug.remote_autostart = 1" >> /etc/php/8.1/cli/conf.d/20-xdebug.ini
 
 # Docker
 RUN apt-get -y install \
    stable"
 RUN apt-get update -y
 RUN apt-get install -y docker-ce docker-ce-cli containerd.io
-RUN ln -s /var/run/docker-host.sock /var/run/docker.sock  
+RUN ln -s /var/run/docker-host.sock /var/run/docker.sock
+
+WORKDIR /var/www/html

.devcontainer/docker-compose.yml

     volumes:
       - .:/workspace:cached
       - /var/run/docker.sock:/var/run/docker-host.sock
+      - ..:/var/www/html
     command: /bin/sh -c "while sleep 1000; do :; done"
     ports:
       - 80:80