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.