fix(GD extension): add GD extension installed for PHP 8.0

laravel-horizon/Dockerfile

@@ -78,10 +78,10 @@ RUN set -eux; if [ ${INSTALL_GNUPG} = true ]; then \
 ARG INSTALL_GD=false
 RUN if [ ${INSTALL_GD} = true ]; then \
    apk add --update --no-cache freetype-dev libjpeg-turbo-dev jpeg-dev libpng-dev; \
-   if [ ${LARADOCK_PHP_VERSION} = "7.4" ]; then \
-      docker-php-ext-configure gd --with-freetype --with-jpeg; \
+   if [ $(php -r "echo PHP_VERSION_ID - PHP_RELEASE_VERSION;") = "80000" ] || [ $(php -r "echo PHP_VERSION_ID - PHP_RELEASE_VERSION;") = "70400" ]; then \
+     docker-php-ext-configure gd --with-freetype --with-jpeg; \
    else \
-      docker-php-ext-configure gd --with-freetype-dir=/usr/lib/ --with-jpeg-dir=/usr/lib/ --with-png-dir=/usr/lib/; \
+     docker-php-ext-configure gd --with-freetype-dir=/usr/lib/ --with-jpeg-dir=/usr/lib/ --with-png-dir=/usr/lib/; \
    fi && \
    docker-php-ext-install gd \
 ;fi