Update env.j2

Set OPEN_AI to matrix_bot_chatgpt_openai_pro

roles/custom/matrix-bot-chatgpt/templates/env.j2

@@ -4,6 +4,7 @@ MATRIX_ACCESS_TOKEN={{ matrix_bot_chatgpt_matrix_access_token }}
 OPENAI_EMAIL={{ matrix_bot_chatgpt_openai_email }}
 OPENAI_PASSWORD={{ matrix_bot_chatgpt_openai_password }}
 OPENAI_LOGIN_TYPE={{ matrix_bot_chatgpt_openai_login_type }}
+OPENAI_PRO={{ matrix_bot_chatgpt_openai_pro }}
 
 # With the @ and :DOMAIN, ie @SOMETHING:DOMAIN
 MATRIX_BOT_USERNAME={{ matrix_bot_chatgpt_matrix_bot_username }}