Add typedoc for debounce

lib/inngest/function/config.ex

@@ -31,6 +31,22 @@ defmodule Inngest.FnOpts do
           cancel_on: cancel_on() | nil
         }
 
+  @typedoc """
+  Options to configure function debounce ([reference](https://www.inngest.com/docs/reference/functions/debounce)).
+
+  **period** - `string` required
+
+  The time period of which to set the limit. The period begins when the first matching event is received. How long to wait before invoking the function with the batch even if it's not full. Current permitted values are from `1s` to `7d (168h)`.
+
+  **key** - `string` optional
+
+  A unique key expression to apply the debounce to. The expression is evaluated for each triggering event.
+
+  Expressions are defined using the [Common Expression Language (CEL)](https://github.com/google/cel-go) with the original event accessible using dot-notation. Examples:
+
+  * Debounce per customer id: `event.data.customer_id`
+  * Debounce per account and email address: `event.data.account_id + "-" + event.user.email`
+  """
   @type debounce() :: %{
           key: binary() | nil,
           period: binary()