Fix non existing Entity issue

Fix the `SimulatorCore::DistanceConditionEvaluation::prerequisite` helper function to work not only with `std::string` but also other types convertible to `std::string` like `openscenario_interpreter::EntityRef`

Signed-off-by: Mateusz Palczuk <mateusz.palczuk@robotec.ai>

openscenario/openscenario_interpreter/include/openscenario_interpreter/simulator_core.hpp

@@ -129,12 +129,12 @@ class SimulatorCore
     static auto prerequisite(
       const FirstType & from_pose_or_entity_name, const SecondType & to_pose_or_entity_name) -> bool
     {
-      if constexpr (std::is_same_v<FirstType, std::string>) {
+      if constexpr (std::is_convertible_v<FirstType, std::string>) {
         if (!core->isEntityExist(from_pose_or_entity_name)) {
           return false;
         }
       }
-      if constexpr (std::is_same_v<SecondType, std::string>) {
+      if constexpr (std::is_convertible_v<SecondType, std::string>) {
         if (!core->isEntityExist(to_pose_or_entity_name)) {
           return false;
         }