Update webhook api readme

chat/matrix/bridges.markdown

@@ -65,10 +65,11 @@ This API translates incoming webhooks into generic webhooks (hookshot). The sour
 
 Base URL: `https://webhooks.mbot.ethz.ch/webhook/grafana/<hook>`
 
-1. Create a new notification channel for the room: **Alerting** > **Notification channels**
-2. Select **Type**: `webhook`
-3. Paste the url into the **Url** field
-4. Disable **Notification settings** > **Include image**
+In [Grafana](https://grafana.phys.ethz.ch) ([Docs](https://readme.phys.ethz.ch/documentation/grafana/#sending-alerts-to-matrix)):
+
+1. Create a contact point for the room: **Alerting** > **Contact points** > **Add contact point**
+2. Add a **Name** and select **Integration**: `Webhook`
+3. Paste the url into the **URL** field
 
 Optional: Select another notification template using a query parameter: `?template=<template>`.
 Refer to the [configuration section](https://gitlab.ethz.ch/isgphys/webhook-to-matrix-hookshot#configuration)
@@ -80,11 +81,10 @@ for details.
 
 Base URL: `https://webhooks.mbot.ethz.ch/webhook/slack/<hook>`
 
-1. Create a new notification channel for the room: **Alerting** > **Notification channels**
-2. Select **Type**: `Slack`
-3. Paste the url into the **Webhook Url** field
-4. Disable **Notification settings** > **Include image**
-5. Optional: Set **Optional Slack settings** > **Username** to `Grafana`
+1. Create a contact point for the room: **Alerting** > **Contact points** > **Add contact point**
+2. Select **Integration**: `Slack`
+3. Paste the url into the **Webhook URL** field
+4. Optional: Set **Optional Slack settings** > **Username** to `Grafana`
 
 
 ## Heisenbridge