integration-docs: Update Gitea for new doc format.

Part of #29592.

zerver/webhooks/gitea/doc.md

@@ -1,21 +1,33 @@
+# Zulip Gitea integration
+
 Receive Gitea notifications in Zulip!
 
+{start_tabs}
+
 1. {!create-channel.md!}
 
 1. {!create-an-incoming-webhook.md!}
 
-1. {!generate-integration-url.md!}
-
-    {!git-webhook-url-with-branches.md!}
+1. {!generate-webhook-url-basic.md!}
 
 1. Go to your repository on Gitea and click on **Settings**. Select
    **Webhooks** on the left sidebar, and click **Add Webhook**.
    Select **Gitea**.
 
-1. Set **Payload URL** to the URL constructed above. Set **Content type**
-   to `application/json`. Select the events you would like to receive
-   notifications for, and click **Add Webhook**.
+1. Set **Payload URL** to the URL generated above. Set **Content type**
+   to `application/json`. Select the [events](#filtering-incoming-events)
+   you would like to receive notifications for, and click **Add Webhook**.
+
+{end_tabs}
 
 {!congrats.md!}
 
 ![](/static/images/integrations/gitea/001.png)
+
+### Configuration options
+
+{!git-branches-additional-feature.md!}
+
+### Related documentation
+
+{!webhooks-url-specification.md!}