message: use string_view
diff: // NOLINT(namespace-envoy)
  #include <string>
  +#include <string_view>
  #include <unordered_map>
  #include "proxy_wasm_intrinsics.h"
  class ExampleRootContext : public RootContext {
  public:
  - explicit ExampleRootContext(uint32_t id, StringView root_id) : RootContext(id, root_id) {}
  + explicit ExampleRootContext(uint32_t id, std::string_view root_id) : RootContext(id, root_id) {}
  bool onStart(size_t) override;
  };
  