[1.x] Use different DB user for Sail (#75)

* Use different DB user for MySQL

* Update InstallCommand.php

Co-authored-by: Taylor Otwell <taylor@laravel.com>

src/Console/InstallCommand.php

@@ -117,8 +117,10 @@ protected function replaceEnvVariables(array $services)
             $environment = str_replace('DB_PORT=3306', "DB_PORT=5432", $environment);
         } else {
             $environment = str_replace('DB_HOST=127.0.0.1', "DB_HOST=mysql", $environment);
+            $environment = str_replace('DB_USERNAME=root', "DB_USERNAME=sail", $environment);
+            $environment = str_replace('DB_PASSWORD=', "DB_PASSWORD=password", $environment);
         }
-        
+
         $environment = str_replace('MEMCACHED_HOST=127.0.0.1', 'MEMCACHED_HOST=memcached', $environment);
         $environment = str_replace('REDIS_HOST=127.0.0.1', 'REDIS_HOST=redis', $environment);