fix: building for debug mode

Author: shirakaba

API/hermes/hermes_napi.cpp

@@ -463,7 +463,7 @@ class NapiStableAddressStack final {
  private:
   // The size of 64 entries per chunk is arbitrary at this point.
   // It can be adjusted depending on perf data.
-  static const size_t ChunkSize = 64;
+  static const constexpr size_t ChunkSize = 64;
 
   llvh::SmallVector<std::unique_ptr<T[]>, ChunkSize> storage_;
   size_t size_{0};