Use Alpine Linux in examples and use default user

Signed-off-by: J0WI <J0WI@users.noreply.github.com>

Author: J0WI

.examples/docker-compose/insecure/mariadb-cron-redis/apache/docker-compose.yml

@@ -13,7 +13,7 @@ services:
       - db.env
 
   redis:
-    image: redis
+    image: redis:alpine
     restart: always
 
   app:

.examples/docker-compose/insecure/mariadb-cron-redis/fpm/app/Dockerfile

@@ -1,3 +1,3 @@
-FROM nextcloud:fpm
+FROM nextcloud:fpm-alpine
 
 COPY redis.config.php /usr/src/nextcloud/config/redis.config.php

.examples/docker-compose/insecure/mariadb-cron-redis/fpm/docker-compose.yml

@@ -13,7 +13,7 @@ services:
       - db.env
 
   redis:
-    image: redis
+    image: redis:alpine
     restart: always
 
   app:

.examples/docker-compose/insecure/mariadb-cron-redis/fpm/web/Dockerfile

@@ -1,3 +1,3 @@
-FROM nginx
+FROM nginx:alpine
 
 COPY nginx.conf /etc/nginx/nginx.conf

.examples/docker-compose/insecure/mariadb-cron-redis/fpm/web/nginx.conf

@@ -1,4 +1,3 @@
-user  www-data;
 worker_processes  1;
 
 error_log  /var/log/nginx/error.log warn;

.examples/docker-compose/insecure/mariadb/fpm/docker-compose.yml

@@ -13,7 +13,7 @@ services:
       - db.env
 
   app:
-    image: nextcloud:fpm
+    image: nextcloud:fpm-alpine
     restart: always
     volumes:
       - nextcloud:/var/www/html

.examples/docker-compose/insecure/mariadb/fpm/web/Dockerfile

@@ -1,3 +1,3 @@
-FROM nginx
+FROM nginx:alpine
 
 COPY nginx.conf /etc/nginx/nginx.conf

.examples/docker-compose/insecure/mariadb/fpm/web/nginx.conf

@@ -1,4 +1,3 @@
-user  www-data;
 worker_processes  1;
 
 error_log  /var/log/nginx/error.log warn;

.examples/docker-compose/insecure/postgres/apache/docker-compose.yml

@@ -2,7 +2,7 @@ version: '3'
 
 services:
   db:
-    image: postgres
+    image: postgres:alpine
     restart: always
     volumes:
       - db:/var/lib/postgresql/data

.examples/docker-compose/insecure/postgres/fpm/docker-compose.yml

@@ -2,15 +2,15 @@ version: '3'
 
 services:
   db:
-    image: postgres
+    image: postgres:alpine
     restart: always
     volumes:
       - db:/var/lib/postgresql/data
     env_file:
       - db.env
 
   app:
-    image: nextcloud:fpm
+    image: nextcloud:fpm-alpine
     restart: always
     volumes:
       - nextcloud:/var/www/html