Relax the SourceLink req. to copy constructible

Previously, the SourceLinkConcept required that the type was is_trivially_copyable (i.e. a type can be copied by memcpy). This makes the frameworks SimIdentifier fail the concept requirements, because it's not. This changes the requirement to simply say is_copy_construcible, a much less stringent criterion.

Core/include/Acts/EventData/SourceLinkConcept.hpp

@@ -40,8 +40,8 @@ namespace concept {
         surface_method_exists,
         "Source link does not have compliant referenceSurface method");
 
-    constexpr static bool copyable = std::is_trivially_copyable_v<T>;
-    static_assert(copyable, "Source link must be trivially copyable");
+    constexpr static bool copyable = std::is_copy_constructible_v<T>;
+    static_assert(copyable, "Source link must be copy constructible");
 
     constexpr static bool value =
         concept ::require<comparison_works, surface_method_exists, copyable>;