Laravel testing with phpunit

How can I make sure that when I'm testing in Laravel with phpunit and for example I want to test my api route /test/1 it uses my test database?

I already made a test connection and changed my phpunit.xml file. I changed DB_CONNECTION to the test connection that I made.

<env name="DB_CONNECTION" value="mysql_testing"/>

But it when I make a post request I receive data from the development database?