Added negative tests and removed few stubs as UI changed

1) few stubs have been removed as they are no longer valid as the hammer cli now uses --id instead of --labels.
2) BadEnv negative test fails currently due to a bug, bug-id updated.
3) Update the test_cv_composite_create test, so that composite content-view has atleast 1 normal cv.
4) Removed few redundant assert, for my tests earlier.