chore: move the templates to their appropriate folders

Dockerfile

@@ -1,6 +1,6 @@
 # syntax=docker/dockerfile:1
 ARG VERSION="3.17"
-FROM alpine:${VERSION} AS builder
+FROM alpine:${VERSION} AS runner
 WORKDIR "/home/librex"
 
 # Docker metadata contains information about the maintainer, such as the name, repository, and support email

docker/nginx/nginx.dockerfile

@@ -1 +1,4 @@
-FROM nginx:stable-alpine
+# syntax=docker/dockerfile:1
+ARG VERSION="3.17"
+FROM alpine:${VERSION} AS builder
+WORKDIR "/home/librex"

docker/php/php.Dockerfile

@@ -1 +1,4 @@
-FROM php:7.4-fpm-alpine
+# syntax=docker/dockerfile:1
+ARG VERSION="3.17"
+FROM alpine:${VERSION} AS builder
+WORKDIR "/home/librex"