MQE-1750: unit tests

[jilu1]

Description

Fixed Issues (if relevant)

1. magento/magento2-functional-testing-framework#<issue_number>: Issue title
2. ...

Contribution checklist

• Pull request has a meaningful description of its purpose
• All commits are accompanied by meaningful commit messages
• All new or changed code is covered with unit/verification tests (if applicable)
• All automated tests passed successfully (all builds on Travis CI are green)
• Changes to Framework doesn't have backward incompatible changes for tests or have related Pull Request with fixes to tests

[coveralls]

Coverage increased (+0.7%) to 53.877% when pulling 9f6cffc on MQE-1750 into 02902f9 on develop.

[coveralls]

Coverage increased (+0.7%) to 53.877% when pulling 9f6cffc on MQE-1750 into 02902f9 on develop.

[coveralls]

Coverage increased (+0.5%) to 53.066% when pulling 68c5576 on MQE-1750 into 5ee8dda on develop.

[KevinBKozan]

Let's change this to just be private $composer; and change setUpBeforeClass() to just setUp().

Since this is initialized only once in the test, the object's state is subject to change due to test's manipulation, which set a bad pattern if we ever do any state tracking in that class in the future.

Also being the class under test, we should really initialize once per test.

[jilu1]

Fixed

[KevinBKozan]

See comment above.

[jilu1]

Fixed

[KevinBKozan]

Unit tests look good to me!

Diffed before/after of magento2ce enabledDirectoryPaths and no difference detected, nice work 👍