Date: add state (#34685)

* Date: add state

* Update source/_integrations/date.markdown

source/_integrations/date.markdown

@@ -17,6 +17,15 @@ The **Date** {% term integration %} is built for the controlling and monitoring
 
 If you are looking for a way to create a similar entity, please take a look at the [Date/Time helper](/integrations/input_datetime).
 
+## The state of a date entity
+
+The state of a date entity is the actual date value.
+
+<p class='img'>
+<img src='/images/integrations/date/state_date.png' alt='Screenshot showing the state of a date in the developer tools' />
+Screenshot showing the state of a date in the developer tools. In the example shown, the state is January 1, 2020; in the format YYYY-MM-DD.
+</p>
+
 ## Actions
 
 ### Date actions
@@ -28,6 +37,6 @@ Available {% term actions %}: `date.set_value`
 Set a new value for the date {% term entity %}.
 
 | Data attribute | Optional | Description                                                                |
-| ---------------------- | -------- | ----------- |
-| `entity_id` | no | String or list of strings that point at `entity_id`'s of dates to control.
-| `date` | no | New date value to set.
+| -------------- | -------- | -------------------------------------------------------------------------- |
+| `entity_id`    | no       | String or list of strings that point at `entity_id`'s of dates to control. |
+| `date`         | no       | New date value to set.                                                     |