Add E2E Testing for Matrix

1) TestPipelineRunMatrixed is an integration test that verifies that a Matrixed PipelineRun succeeds with both `matrix params` and `matrix include params`. It also tests array indexing and whole array replacements by consuming results produced by other PipelineTasks.

2) TestPipelineRunMatrixedFailed is an integration test with a Matrixed PipelineRun that contains an unsuccessful TaskRun. This test verifies that the taskRun will fail, which will cause the entire PipelineRun to fail.2) TestPipelineRunMatrixedFailed is an integration test with a Matrixed PipelineRun that contains an unsuccessful TaskRun. This test verifies that the taskRun will fail, which will cause the entire PipelineRun to fail.