Update limits.mdx (#21935)

limits clarification

Author: kathayl

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

@@ -15,7 +15,7 @@ import { Render, Plan } from "~/components";
 | Feature                                | Limit           |
 | -------------------------------------- | --------------- |
 | Concurrent browsers per account (Workers Binding API only)        | 3 per account   |
-| New browser instances per minute       | 3 per minute    |
+| New browser instances per minute (Workers Binding API only)      | 3 per minute    |
 | Browser timeout                        | 60 seconds [^2] |
 | Total requests per min (REST API only) | 6 per minute    |
 
@@ -26,7 +26,7 @@ import { Render, Plan } from "~/components";
 | Feature                                | Limit               |
 | -------------------------------------- | ------------------- |
 | Concurrent browsers per account (Workers Binding API only)        | 10 per account [^1] |
-| New browser instances per minute       | 10 per minute [^1]  |
+| New browser instances per minute (Workers Binding API only)       | 10 per minute [^1]  |
 | Browser timeout                        | 60 seconds [^2][^1] |
 | Total requests per min (REST API only) | 60 per minute       |