Disable C4512 in uncaught_exceptions(_np).cpp

test/uncaught_exceptions_np.cpp

@@ -20,6 +20,10 @@
 
 #include <boost/core/lightweight_test.hpp>
 
+#if defined(_MSC_VER)
+# pragma warning(disable: 4512) // assignment operator could not be generated
+#endif
+
 struct my_exception1 {};
 struct my_exception2 {};