docs: Update Generic scraper doc (#1941)

* Update Generic scraper doc

- Highlight the fact that the filter parameter is optional.
- Inform people about the filter syntax (#1740).
- Inform people about the other optional fields available (#1849).

* fix line length

* Update docs/configuration/v2.x/metrics/generic-azure-resource.md

* Update docs/configuration/v2.x/metrics/generic-azure-resource.md

* Update docs/configuration/v2.x/metrics/generic-azure-resource.md

Co-authored-by: Tom Kerkhove <[email protected]>

docs/configuration/v2.x/metrics/generic-azure-resource.md

@@ -9,14 +9,19 @@ title: Generic Azure Resource Declaration
 
 You can declare to scrape a generic Azure resource via the `Generic` resource type.
 
-The following fields need to be provided:
+Promitor simplifies defining resource URIs by using the subscription & resource
+group defined in `azureMetadata` so that your configuration is small & readable.
+
+Mandatory fields :
 
 - `resourceUri` - The uri of the Azure resource to scrape.
-- `filter` - The filter to use to have fine-grained metrics. Example:
-  `EntityName eq 'orders'`
 
-Promitor simplifies defining resource uris by using the subscription & resource
-group defined in `azureMetadata` so that your configuration is small & readable.
+Optional fields :
+
+- `resourceGroupName` - the resource group for this resource. It overrides the one defined in `azureMetadata`.
+- `subscriptionId` - the subscription ID for this resource. It overrides the one defined in `azureMetadata`.
+- `filter` - The filter to use to have fine-grained metrics. Example: `EntityName eq 'orders'`.
+   See [Azure Monitor REST API Filter Syntax](https://docs.microsoft.com/en-us/rest/api/monitor/filter-syntax).
 
 Example:
 
@@ -29,12 +34,15 @@ azureMetricConfiguration:
   aggregation:
     type: Total
 resources:
-# Will scrape subscriptions/<sub>/resourceGroups/<rg>/providers/Microsoft.ServiceBus/namespaces/promitor-messaging
-# Where 'sub' & 'rg' are coming from azureMetadata
-- resourceUri: Microsoft.ServiceBus/namespaces/promitor-messaging
+# Will scrape subscriptions/<sub>/resourceGroups/<rg>/providers/Microsoft.ServiceBus/namespaces/my-promitor-messaging
+# Where <sub> & <rg> are coming from azureMetadata
+- resourceUri: Microsoft.ServiceBus/namespaces/my-promitor-messaging
   filter: EntityName eq 'orders'
-- resourceUri: Microsoft.ServiceBus/namespaces/promitor-messaging
-  filter: EntityName eq 'items'
+# Will scrape subscriptions/<sub>/resourceGroups/<rg>/providers/Microsoft.ServiceBus/namespaces/my-other-promitor-messaging
+# Where <sub> & <rg> are coming from the definition of this resource.
+- resourceUri: Microsoft.ServiceBus/namespaces/my-other-promitor-messaging
+  subscriptionId: example-subscription
+  resourceGroupName: example-resource-group
 ```
 
 <!-- markdownlint-disable MD033 -->