Add engines for psychology

Status
Done
Release date
Sep 3, 2021

2021/9/3 The psychology engine is available by registering for Langsmith Premium plan. This engine is also available during the free trial period (7 days) when you register for the Free plan, along with the medical, chemistry, biology, machine learning, image processing, and natural language processing fields. You can also try the psychology engine during the free trial period (7 days) when you register for the Free Plan.