Fix typos in file name (#5330)

source/_components/sensor.gitter.markdown

@@ -15,19 +15,27 @@ ha_release: 0.47
 
 This `gitter` sensor allows one to monitor a [Gitter.im](https://gitter.im) chatroom for unread messages.
 
+## {% linkable_title Configuration %}
+
 Visit [Gitter Developer Apps](https://developer.gitter.im/apps) to retrieve your "Personal Access Token".
 
 To use a Gitter sensor in your installation, add the following to your `configuration.yaml` file:
 
 ```yaml
-# Example configuration.yml entry
+# Example configuration.yaml entry
 sensor:
   - platform: gitter
     api_key: YOUR_API_TOKEN
 ```
 
-Configuration variables:
-
-- **api_key** (*Required*): Your Gitter.im API token.
-- **room** (*Optional*): Gitter room to monitor. Defaults to `home-assistant/home-assistant`
-
+{% configuration %}
+api_key:
+  description: Your Gitter.im API token.
+  required: true
+  type: string
+room:
+  description: Gitter room to monitor.
+  required: false
+  type: string
+  default: home-assistant/home-assistant
+{% endconfiguration %}