[skip-tests] Disable flaky barrier tests (#510)

Author: miscco

libcudacxx/.upstream-tests/test/heterogeneous/barrier_parity.cuda.pass.cpp

@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: nvrtc, pre-sm-70
+// UNSUPPORTED: true
 
 // uncomment for a really verbose output detailing what test steps are being launched
 // #define DEBUG_TESTERS

libcudacxx/.upstream-tests/test/heterogeneous/barrier_parity.std.pass.cpp

@@ -8,6 +8,7 @@
 //===----------------------------------------------------------------------===//
 
 // UNSUPPORTED: nvrtc, pre-sm-70
+// UNSUPPORTED: true
 
 // uncomment for a really verbose output detailing what test steps are being launched
 // #define DEBUG_TESTERS