Update an environment

Updates specific environment properties, such as its name and variables. **Note:** - You can only perform one type of operation at a time. For example, you cannot perform an `add` and `replace` operation in the same call. - The request body size cannot exceed the maximum allowed size of 30MB. - If you receive an HTTP `411 Length Required` error response, manually pass the `Content-Length` header and its value in the request header. - To add a description to an existing variable, use the `add` operation. - Only [shared variable](https://learning.postman.com/docs/use/send-requests/variables/variables/#share-variable-values) values can be modified through the Postman API. A shared variable is an environment variable with its value synced and stored in the Postman cloud, and can be accessed by your teammates in the environment's workspace.