Add support for tests included in a test class via a trait

[chiefmyron]

Laravel has a number of test case classes where the actual tests are defined in traits that are used within the class definition:

Update the test file parser to identify traits used within a Test class, and add any test methods within the trait as test items.

[chiefmyron]

Test being executed from an included trait is reported in the teamcity logs as follows:

##teamcity[testSuiteStarted name='Illuminate\Tests\Integration\Database\EloquentTransactionWithAfterCommitTest' locationHint='php_qn://C:\Development\PHP\laravel\framework\tests\Integration\Database\EloquentTransactionWithAfterCommitTest.php::\Illuminate\Tests\Integration\Database\EloquentTransactionWithAfterCommitTest' flowId='12148']
##teamcity[testStarted name='testObserverIsCalledOnTestsWithAfterCommit' locationHint='php_qn://C:\Development\PHP\laravel\framework\tests\Integration\Database\EloquentTransactionWithAfterCommitTests.php::\Illuminate\Tests\Integration\Database\EloquentTransactionWithAfterCommitTest::testObserverIsCalledOnTestsWithAfterCommit' flowId='12148']
##teamcity[testFinished name='testObserverIsCalledOnTestsWithAfterCommit' duration='320' flowId='12148']

[chiefmyron]

This could be tricker than originally estimated. Taking the example class in the above description, there are two traits used by the test. However, both of these include additional traits, down multiple levels:

• Illuminate\Tests\Integration\Database\EloquentTransactionWithAfterCommitTests
  • Orchestra\Testbench\Concerns\WithLaravelMigrations
    • Orchestra\Testbench\Concerns\InteractsWithWorkbench
      • Orchestra\Testbench\Concerns\InteractsWithPest
        • Orchestra\Testbench\Concerns\InteractsWithPHPUnit
          • Orchestra\Testbench\Concerns\InteractsWithTestCase
        • Orchestra\Testbench\Concerns\InteractsWithTestCase
      • Orchestra\Testbench\Concerns\InteractsWithPHPUnit
        • Orchestra\Testbench\Concerns\InteractsWithTestCase
      • Orchestra\Testbench\Concerns\InteractsWithTestCase
  • Illuminate\Foundation\Testing\DatabaseMigrations
    • Illuminate\Foundation\Testing\Traits\CanConfigureMigrationCommands

The vast majority of these nested traits do not actually include test methods, but are just helper methods. Will need to recursively parse potentially quite deep nested traits.

Could look at caching traits, but that has issues of its own - traits aren't included in the patterns used by the file watchers, since they don't need to conform to anything defined in the phpunit.xml configuration. If the trait is modified by the user, the extension has no way of picking up those changes, unless we add new watchers for each trait parsed. Either option could introduce some significant performance degredation.