Fix build problem

phpfpm/Dockerfile

@@ -1,6 +1,6 @@
 FROM php:7.4-fpm-alpine
 
-RUN apk add --update --no-cache --virtual \
+RUN apk add --update --no-cache \
         build-base \
         autoconf \
         jpeg-dev \
@@ -24,7 +24,4 @@ RUN docker-php-ext-configure gd --with-freetype=/usr/include/ --with-jpeg=/usr/i
         pdo_mysql \
         mbstring \
     && pecl install xdebug \
-    && docker-php-ext-enable xdebug
-
-RUN rm -r /tmp/* /var/cache/* \
-    && docker-php-source delete
+    && docker-php-ext-enable xdebug