Update .env.example

.env.example

@@ -15,9 +15,9 @@ LOG_CHANNEL=stack
 DB_CONNECTION=mysql
 DB_HOST=127.0.0.1
 DB_PORT=3306
-DB_DATABASE=
-DB_USERNAME=
-DB_PASSWORD=
+DB_DATABASE=pixelfed
+DB_USERNAME=pixelfed
+DB_PASSWORD=pixelfed
 
 BROADCAST_DRIVER=log
 CACHE_DRIVER=redis