add db type to template

.env.template

@@ -2,4 +2,5 @@ JWT_SECRET=something
 COOKIE_SECRET=something
 
 DATABASE_URL="postgres://localhost/medusa-store"
+DATABASE_TYPE="postgres"
 REDIS_URL=redis://localhost:6379

medusa-config.js

@@ -30,7 +30,7 @@ const STORE_CORS = process.env.STORE_CORS || "http://localhost:8000";
 
 const DATABASE_URL =
   process.env.DATABASE_URL || "postgres://localhost/medusa-db";
-  
+
 const REDIS_URL = process.env.REDIS_URL || "redis://localhost:6379";
 
 const plugins = [