Sed should be -i -e, not -ie

Dockerfile

@@ -4,7 +4,7 @@
 FROM php:8.1-fpm-alpine
 
 # Change to http respositories, so they we can cache the install packages
-RUN if [ -n ${HTTP_PROXY} ] ; then sed -ie s'/https/http/' /etc/apk/repositories; fi
+RUN if [ -n ${HTTP_PROXY} ] ; then sed -i -e s'/https/http/' /etc/apk/repositories; fi
 COPY docker/pecl_install /usr/local/bin/pecl_install
 
 # Tune PHP