Added SDL_GetGlobalProperties()

We'll undoubtedly want to have global properties available

src/dynapi/SDL_dynapi.sym

@@ -922,6 +922,7 @@ SDL3_0.0.0 {
     SDL_GetDisplayProperties;
     SDL_SetPropertyWithCleanup;
     SDL_SetX11EventHook;
+    SDL_GetGlobalProperties;
     # extra symbols go here (don't modify this line)
   local: *;
 };