Quench deprecation warnings when compiling the tutorials.

Author: bluescarni

tutorials/CMakeLists.txt

@@ -10,6 +10,7 @@ function(ADD_PAGMO_TUTORIAL arg1)
     # Set the minimum C++ standard to C++17
     target_compile_features(${arg1} PRIVATE cxx_std_17)
     set_property(TARGET ${arg1} PROPERTY CXX_EXTENSIONS NO)
+    target_compile_definitions(${arg1} PRIVATE BOOST_ALLOW_DEPRECATED_HEADERS)
     add_test(${arg1} ${arg1})
 endfunction()