doc: amplify warning for execute callback

Add specific recommendation not to use the
to the napi-env parameter in napi_async_execute_callback

doc/api/n-api.md

@@ -462,7 +462,10 @@ typedef void (*napi_async_execute_callback)(napi_env env, void* data);
 Implementations of this type of function should avoid making any N-API calls
 that could result in the execution of JavaScript or interaction with
 JavaScript objects. Most often, any code that needs to make N-API
-calls should be made in `napi_async_complete_callback` instead.
+calls should be made in `napi_async_complete_callback` instead. The
+current recommendation is to avoid all usage of the
+napi_env parameter in the execute callback as it will most
+likely cause JavaScript to be executed.
 
 #### napi_async_complete_callback
 <!-- YAML
@@ -4027,7 +4030,10 @@ task respectively.
 The `execute` function should avoid making any N-API calls
 that could result in the execution of JavaScript or interaction with
 JavaScript objects. Most often, any code that needs to make N-API
-calls should be made in `complete` callback instead.
+calls should be made in `complete` callback instead. The
+current recommendation is to avoid all usage of the
+napi_env parameter in the execute callback as it will most
+likely cause JavaScript to be executed.
 
 These functions implement the following interfaces: