Clique kernel support (#295)

* Adding experimental clique-based kernels (opt-in only)

Co-authored-by: Stanley Tsang <stanley.tsang@amd.com>
Co-authored-by: Gilbert Lee <gilbert.lee@amd.com>
Co-authored-by: Wenkai Du <43822138+wenkaidu@users.noreply.github.com>

test/test_AllReduce.cpp

@@ -58,6 +58,6 @@ namespace CorrectnessTests
                                 testing::Values(2,3,4,5,6,7,8),
                                 // In-place or not
                                 testing::Values(false, true),
-                                testing::Values("")),
+                                testing::Values("RCCL_ENABLE_CLIQUE=0", "RCCL_ENABLE_CLIQUE=1")),
                             CorrectnessTest::PrintToStringParamName());
 } // namespace