PHPUnit FilterTest failing incorrectly

The test was using a function to returning the 1st 50 issues for all
projects. In a DB containing more than 50 issues, the test would fail
incorrectly.

Now using a filter on the current project only.
PHPUnit HelperTest fix error 4096

Commit 5458f7020999317b35f403fa2a0e477d6182ec12 changed function
helper_array_transpose() signature, the argument MUST be an array so it
does not make sense for the unit test to cover NULL, Scalar and Object
types.