One .env and updated dockerfile

gitea/.env.db.example

@@ -1 +0,0 @@
-MYSQL_PASSWORD=<changeme>

gitea/.env.example

@@ -1 +1,2 @@
+DB_PASSWD=<changeme>
 PORT=<changeme>

gitea/.env.gitea.example

@@ -1 +0,0 @@
-DB_PASSWD=<changeme>

gitea/docker-compose.yml

@@ -3,17 +3,17 @@ version: "2"
 services:
   server:
     image: gitea/gitea:latest
-    env_file: .env.gitea
     environment:
       - USER_UID=1000
       - USER_GID=1000
       - DB_TYPE=mysql
-      - DB_HOST=db:5432
+      - DB_HOST=db:3306
       - DB_NAME=gitea
       - DB_USER=gitea
+      - DB_PASSWD=${DB_PASSWD}
     restart: unless-stopped
     links:
-      - db
+      - db:db
     volumes:
       - gitea:/data
       - /etc/timezone:/etc/timezone:ro
@@ -30,11 +30,11 @@ services:
     restart: unless-stopped
     volumes:
       - db:/var/lib/mysql
-    env_file: .env.db
     environment:
       - MYSQL_RANDOM_ROOT_PASSWORD=yes
       - MYSQL_DATABASE=gitea
       - MYSQL_USER=gitea
+      - MYSQL_PASSWORD=${DB_PASSWD}
 
 volumes:
   db: