Running tests takes too long

[HeathNaylor]

When running from my local machine I return in ~5 seconds, when I run tests from the docker container it ends up taking ~3 minutes.

From docker run command:

docker run -v $(pwd):/app --rm phpunit/phpunit -c /app/phpunit.xml
PHPUnit 6.5.5 by Sebastian Bergmann, Julien Breux (Docker) and contributors.

Runtime:       PHP 7.1.12 with Xdebug 2.5.5
Configuration: /app/phpunit.xml

.......................................................           55 / 55 (100%)

Time: 2.65 minutes, Memory: 14.00MB

vs

$ vendor/bin/phpunit
PHPUnit 6.3.1 by Sebastian Bergmann and contributors.

Runtime:       PHP 7.0.25 with Xdebug 2.5.5
Configuration: ~/phpunit.xml

.......................................................           55 / 55 (100%)

Time: 5.15 seconds, Memory: 16.00MB