Error when running dart run build_runner on the example

[tyler-jewell]

Environment variable not found for field apiKey.
package:example/env/env.dart:9:23
╷
9 │ static const String apiKey = _Env.apiKey;
│ ^^^^^^
╵

I am currently changing the ENV var name to resolve this.

Before:

OPEN_AI_API_KEY=

After:

API_KEY=