docs: add api scope to dev tunnel docs (#747)

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## Changes

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docs/infrastructure/dev-tunnel/SETUP.md

@@ -13,14 +13,16 @@ Make sure to run `nix-shell` for all subsequent commands.
 
 -   Docker
 -   Linode API Key
+    -   Scope: `Linodes: Read/Write, Firewall: Read/Write`
 
 ## Step 1: Create Dev Tunnel
 
 ```sh
 task dev-tunnel:up
 ```
 
-This will prompt you to past your Linode API token.
+This will prompt you to past your Linode API token. Running this will create a
+new `Nanode 1 GB` instance on Linode.
 
 Once complete, this will print an IP to your console like: