Merge pull request #252555 from ChristineWanjau/cwanjau/addSelectionModeToPullTaskDocs

Update to pull task docs to add new selection mode parameter

Author: v-dirichards

articles/azure-app-configuration/media/azure-app-configuration-parameters.png

@@ -84,8 +84,10 @@ The following parameters are used by the Azure App Configuration task:
 
 - **Azure subscription**: A drop-down containing your available Azure service connections. To update and refresh your list of available Azure service connections, press the **Refresh Azure subscription** button to the right of the textbox.
 - **App Configuration Endpoint**: A drop-down that loads your available configuration stores endpoints under the selected subscription. To update and refresh your list of available configuration stores endpoints, press the **Refresh App Configuration Endpoint** button to the right of the textbox.
+- **Selection Mode**: Specifies how the key-values read from a configuration store are selected. The 'Default' selection mode allows the use of key and label filters. The 'Snapshot' selection mode allows key-values to be selected from a snapshot. Default value is **Default**.
 - **Key Filter**: The filter can be used to select what key-values are requested from Azure App Configuration. A value of * will select all key-values. For more information on, see [Query key values](concept-key-value.md#query-key-values).
 - **Label**: Specifies which label should be used when selecting key-values from the App Configuration store. If no label is provided, then key-values with the no label will be retrieved. The following characters are not allowed: , *.
+-**Snapshot Name**: Specifies snapshot from which key-values should be retrieved in Azure App Configuration.
 - **Trim Key Prefix**: Specifies one or more prefixes that should be trimmed from App Configuration keys before setting them as variables. Multiple prefixes can be separated by a new-line character.
 - **Suppress Warning For Overridden Keys**: Default value is unchecked. Specifies whether to show warnings when existing keys are overridden. Enable this option when it is expected that the key-values downloaded from App Configuration have overlapping keys with what exists in pipeline variables.