This makes ada's target compile options private under Windows. (#599)

Author: lemire

src/CMakeLists.txt

@@ -16,7 +16,7 @@ if(MSVC)
     target_compile_options(ada INTERFACE /W0 /sdl)
     set(ADA_LEGACY_VISUAL_STUDIO TRUE)
   else()
-    target_compile_options(ada INTERFACE /WX /W3 /sdl /w34714) # https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warning-level-4-c4714?view=vs-2019
+    target_compile_options(ada PRIVATE /WX /W3 /sdl /w34714) # https://docs.microsoft.com/en-us/cpp/error-messages/compiler-warnings/compiler-warning-level-4-c4714?view=vs-2019
   endif()
 else(MSVC)
   if(NOT WIN32)