Allow skipping of BLT's own PHPUnit tests

[geerlingguy]

When I run this command:

blt tests:phpunit

I get the following output:

$ blt tests:phpunit
Buildfile: /Users/jeff.geerling/Sites/acquia/projectname/vendor/acquia/blt/phing/build.xml

blt > tests:phpunit:

   [delete] Deleting directory /Users/jeff.geerling/Sites/acquia/projectname/reports/phpunit
    [mkdir] Created dir: /Users/jeff.geerling/Sites/acquia/projectname/reports/phpunit
  [phpunit] Testsuite: Project\Tests\Redirect\RedirectTest
  [phpunit] Tests run: 1, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 0.00229 s
  [phpunit] Testsuite: Acquia\Blt\Tests\BltProject\BehatTest
  [phpunit] Tests run: 1, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 0.00187 s
  [phpunit] Testsuite: Acquia\Blt\Tests\BltProject\BuildTest
  [phpunit] Tests run: 1, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 0.00086 s
Executing "/Users/jeff.geerling/Sites/acquia/projectname/vendor/bin/drush status --format=json" in /Users/jeff.geerling/Sites/acquia/projectname/docroot 
Executing "/Users/jeff.geerling/Sites/acquia/projectname/vendor/bin/drush status --format=json" in /Users/jeff.geerling/Sites/acquia/projectname/docroot/sites/default 
  [phpunit] Testsuite: Acquia\Blt\Tests\BltProject\DrushTest
  [phpunit] Tests run: 1, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 0.53019 s
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'This is a bad commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo '123: This is a bad commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'PROJECTNAME: This is a bad commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'PROJECTNAME-123 This is a bad commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'PROJECTNAME-123: This is a bad commit' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'PROJECTNAME-123: Hello.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'NOT-123: This is a bad commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'PROJECTNAME-123: This is a good commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
Executing "mkdir -p /Users/jeff.geerling/Sites/acquia/projectname/tmp && echo 'PROJECTNAME-123: This is an exceptionally long--seriously, really, really, REALLY long, but still good commit.' > /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg && /Users/jeff.geerling/Sites/acquia/projectname/.git/hooks/commit-msg /Users/jeff.geerling/Sites/acquia/projectname/tmp/blt_commit_msg 2>&1" 
  [phpunit] Testsuite: Acquia\Blt\Tests\BltProject\GitTasksTest::testGitHookCommitMsg
  [phpunit] Tests run: 9, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 2.43991 s
  [phpunit] Testsuite: Acquia\Blt\Tests\BltProject\GitTasksTest
  [phpunit] Tests run: 11, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 6.51344 s
  [phpunit] Testsuite: Acquia\Blt\Tests\BltProject\SettingsTest
  [phpunit] Tests run: 1, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 0.00035 s
  [phpunit] Total tests run: 16, Failures: 0, Errors: 0, Incomplete: 0, Skipped: 0, Time elapsed: 7.05550 s
     [echo] PHPUnit Report is available at /Users/jeff.geerling/Sites/acquia/projectname/reports/phpunit/phpunit-noframes.html

BUILD FINISHED

Total time: 7.6140 seconds

And I expected this to happen:

• Only my own tests should be run (not all the BLT built-in tests).

[grasmash]

BLT's PHPUnit tests have been removed from this target by #998