image editing does not work

Hello Community,

I am currently using a docker setup with 7.4-fpm-alpine as my linux distribution in a docker container. I want to edit images inside of WordPress, but the warning tells me “Image rotation is not supported by your web host.”.
I have tried to add php-gd like here Gideon-php-gd, but with the supported packages for alpine in my php.dockerfile by adding the commands, but it did not change anything.

php.dockerfile:

FROM php:7.4-fpm-alpine

RUN docker-php-ext-install mysqli pdo pdo_mysql && docker-php-ext-enable pdo_mysql

RUN apk update \
 && apk add \
    build-base \
    imagemagick \
	gd \

If you need the docker-compose.yml or anything else tell me. I am quite new to Docker, so maybe there is an easy fix, but I am to blind to see.

Thanks in Advance!

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