S01E03 Missing info about OPENAI_API_KEY

[Sumerin]

Update markdown with OPENAI_API_KEY for

S01E03

Langfuse

Ten przykład wymaga uzupełnienia pliku .env o wartości LANGFUSE_PUBLIC_KEY, LANGFUSE_SECRET_KEY oraz LANGFUSE_HOST. Można je uzyskać zakładając bezpłatne konto na Langfuse.

without it we receive

error: 401 You didn't provide an API key. You need to provide your API key in an                                   Authorization header using Bearer auth (i.e. Authorization: Bearer YOUR_KEY), o                                  r as the password field (with blank username) if you're accessing the API from y                                  our browser and are prompted for a username and password. You can obtain an API                                   key from https://platform.openai.com/account/api-keys.
      at new OpenAIError (1:28)
      at new APIError (/usr/lib/bun/node_modules/openai/error.mjs:7:9)
      at new AuthenticationError (/usr/lib/bun/node_modules/openai/error.mjs:96:                                  9)
      at generate (/usr/lib/bun/node_modules/openai/error.mjs:44:20)
      at /usr/lib/bun/node_modules/openai/core.mjs:322:30