chore(docs): improve security documentation (#59)

Author: stainless-app[bot]

Diff for: option/requestoption.go

@@ -24,6 +24,8 @@ import (
 type RequestOption = requestconfig.RequestOption
 
 // WithBaseURL returns a RequestOption that sets the BaseURL for the client.
+//
+// For security reasons, ensure that the base URL is trusted.
 func WithBaseURL(base string) RequestOption {
 	u, err := url.Parse(base)
 	if err != nil {