When I try to get it running without docker, I get the following error: `Environment variable not found: "DATABASE_URL".` My `.env` file looks like this: ``` KERNEL_CLASS=App\Kernel APP_SECRET=s$cretf0rt3st SYMFONY_DEPRECATIONS_HELPER=999999 DATABASE_URL='mysql://root:@localhost:3306/test' ``` I'm new to symfony and I can't figure out the problem.