Update assistant-setup-inbound.mdx (#105)

[Docs] small fix - fix broken link to provider keys

fern/snippets/quickstart/dashboard/assistant-setup-inbound.mdx

@@ -55,14 +55,14 @@
 
     <AccordionGroup>
       <Accordion title="Set Your OpenAI Provider Key (optional)" icon="key" iconType="solid">
-        Before we proceed, we can set our [provider key](customization/provider-keys) for OpenAI (this is just your OpenAI secret key).
+        Before we proceed, we can set our [provider key](https://docs.vapi.ai/customization/provider-keys) for OpenAI (this is just your OpenAI secret key).
 
         <Note>
           You can see all of your provider keys in the "Provider Keys" dashboard tab. You can also go
           directly to [dashboard.vapi.ai/keys](https://dashboard.vapi.ai/keys).
         </Note>
 
-        Vapi uses [provider keys](customization/provider-keys) you provide to communicate with LLM, TTS, & STT vendors on your behalf. It is most ideal that we set keys for the vendors we intend to use ahead of time.
+        Vapi uses [provider keys](https://docs.vapi.ai/customization/provider-keys) you provide to communicate with LLM, TTS, & STT vendors on your behalf. It is most ideal that we set keys for the vendors we intend to use ahead of time.
 
         <Frame caption="We set our provider key for OpenAI so Vapi can make requests to their API.">
           <img src="../static/images/quickstart/dashboard/model-provider-keys.png" />