Deallocate the YogaConfig memory with correct method

Summary: We've mistakenly used `free()` to free the memory, where `delete` should have been used

Reviewed By: davidaurelio

Differential Revision: D9042347

fbshipit-source-id: e15cec0f498409066521a6de1e3fe4b7404ec46c

yoga/Yoga.cpp

@@ -369,7 +369,7 @@ YGConfigRef YGConfigNew(void) {
 }
 
 void YGConfigFree(const YGConfigRef config) {
-  free(config);
+  delete config;
   gConfigInstanceCount--;
 }