[testsuite] Skip an already failing test on MacOS.

Due to some libcxx changes to inlining, this now also crashes,
so it gets reported as "failure" by the bot. This commit doesn't
really change the status quo, just placates the bots.

llvm-svn: 345668

lldb/packages/Python/lldbsuite/test/lang/cpp/stl/TestSTL.py

@@ -26,6 +26,7 @@ class STLTestCase(TestBase):
         self.line = line_number(
             self.source, '// Set break point at this line.')
 
+    @skipIf
     @expectedFailureAll(bugnumber="llvm.org/PR36713")
     def test(self):
         """Test some expressions involving STL data types."""