Refactor mapping driver tests

[IonBazan]

Change Request

Mapping drivers tests should be refactored to reduce code duplication and make sure that all mapping features are tested for each driver and the derived tests for each driver contain only the driver-specific assertions (all general assertions should be in base test cases).

• Merge tests from tests/Doctrine/ODM/MongoDB/Tests/Mapping/Driver/AbstractDriverTest.php and tests/Doctrine/ODM/MongoDB/Tests/Mapping/AbstractMappingDriverTest.php and put fixture documents in separate files
• Merge tests/Doctrine/ODM/MongoDB/Tests/Mapping/AbstractAnnotationDriverTest.php into tests/Doctrine/ODM/MongoDB/Tests/Mapping/AbstractMappingDriverTest.php

[stale]

This issue has been automatically marked as stale because it has not had any recent activity. It will be closed in a week if no further activity occurs. Thank you for your contributions.

[IonBazan]

Closing as duplicate of #2348. My bad.