v1.19.0

Fix issue introduced in v1.18.1 with packages being moved to require-dev.
New projects that depend on alleyinteractive/mantle-framework should require on the newly created mantle-framework/testing-dependencies package. Projects that depend on mantle-framework/testkit are not affected. Because mantle-framework/testing-dependencies also requires PHPUnit, you can also drop that as a dependency if you were requiring it directly.

To upgrade your project, run the following commands:

# If you were requiring PHPUnit directly. 
composer remove phpunit/phpunit --dev

# Require the new testing dependencies package. 
composer require alleyinteractive/mantle-framework/testing-dependencies --dev

Projects that depend only on Mantle Testkit (mantle-framework/testkit) are not affected.