docs(notifications): add more documentation for notifications (#1856)

This PR adds more documentation methods for notifications. Most of it is taken from the Overseerr
documentation.

docs/using-jellyseerr/notifications/ntfy.md

@@ -0,0 +1,29 @@
+---
+title: ntfy.sh
+description: Configure ntfy.sh notifications.
+sidebar_position: 6
+---
+
+# ntfy.sh
+
+## Configuration
+
+### Server Root URL
+
+Set this to the URL of your ntfy.sh server.
+
+### Topic
+
+Set this to the topic you want to send notifications to.
+
+### Username + Password authentication (optional)
+
+Set this to the username and password for your ntfy.sh server.
+
+### Token authentication (optional)
+
+Set this to the token for your ntfy.sh server.
+
+:::info
+Please refer to the [ntfy.sh API documentation](https://docs.ntfy.sh/) for more details on configuring these notifications.
+:::