Bump macOS target to 10.13.0

Apparently required for `std::visit`

Author: glebm

CMakeLists.txt

@@ -395,9 +395,9 @@ if(APPLE)
     set(MACOSX_BUNDLE_REQUIRED_PLATFORM IPhoneOS)
     set_target_properties(${BIN_TARGET} PROPERTIES XCODE_ATTRIBUTE_TARGETED_DEVICE_FAMILY "1,2")
     set(CMAKE_OSX_DEPLOYMENT_TARGET "9.0")
-  elseif(DARWIN_MAJOR_VERSION GREATER_EQUAL 16)
+  elseif(DARWIN_MAJOR_VERSION GREATER_EQUAL 17)
     set(MACOSX_BUNDLE_REQUIRED_PLATFORM Carbon)
-    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.12.0")
+    set(CMAKE_OSX_DEPLOYMENT_TARGET "10.13.0")
   endif()
   if(DARWIN_MAJOR_VERSION VERSION_LESS 9)
     # Finder on OSX Tiger can only handle icns files with up to 128x128 icons.