Update limits.mdx (#21684)

* Update limits.mdx

info on future pricing/billing

* Update limits.mdx

Author: kathayl

src/content/docs/browser-rendering/platform/limits.mdx

@@ -38,6 +38,7 @@ import { Render, Plan } from "~/components";
 
 While the limits above define the maximum number of concurrent browser sessions per account, in practice you may not need to hit these limits. Browser sessions close automatically—by default, after 60 seconds of inactivity or upon task completion—so if each session finishes its work before a new request comes in, the effective concurrency is lower. This means that most workflows do not require very high concurrent browser limits.
 
+## Pricing
 
-
+Browser Rendering service is currently available at no cost up to the limits specified above **until billing begins**. Pricing to be announced and we will provide advance notice before any billing begins.