feat: use COPY --exclude in Dockerfile

Author: 7-zete-7

Dockerfile

@@ -84,8 +84,7 @@ RUN set -eux; \
 	composer install --no-cache --prefer-dist --no-dev --no-autoloader --no-scripts --no-progress
 
 # copy sources
-COPY --link . ./
-RUN rm -Rf frankenphp/
+COPY --link --exclude=frankenphp/ . ./
 
 RUN set -eux; \
 	mkdir -p var/cache var/log; \