GenEx: Restore evaluation context for conditional transitive properties

In commit e8010b67c7 (cmGeneratorExpressionDAGChecker: Make local
generator available in constructor, 2024-04-25, v3.30.0-rc1~172^2~6)
we accidentally failed to preserve `EvaluateInterfaceProperty`'s
consistency with `TargetPropertyNode::Evaluate`.  Fix its local
generator selection to match the evaluation context.

Source/cmGeneratorTarget_TransitiveProperty.cxx

@@ -114,7 +114,7 @@ std::string cmGeneratorTarget::EvaluateInterfaceProperty(
     prop,
     nullptr,
     dagCheckerParent,
-    this->LocalGenerator,
+    context->LG,
     context->Config,
     context->Backtrace,
   };