docs: Add documentation to store config on server via apps.config option (#2982)

Author: hiennguyen92

README.md

@@ -163,7 +163,9 @@ Parse Dashboard is continuously tested with the most recent releases of Node.js
 | `apps.scripts.executionBatchSize`      | Integer             | yes      | `1`     | `10`                                             | The batch size with which a script should be executed on all selected objects. For example, with 50 objects selected, a batch size of 10 means the script will run on 10 objects in parallel, running a total of 5 batches in serial. |
 | `apps.scripts.showConfirmationDialog`  | Bool                | yes      | `false` | `true`                                           | Is `true` if a confirmation dialog should be displayed before the script is executed, `false` if the script should be executed immediately.                                                                                           |
 | `apps.scripts.confirmationDialogStyle` | String              | yes      | `info`  | `critical`                                       | The style of the confirmation dialog. Valid values: `info` (blue style), `critical` (red style).                                                                                                                                      |
-| `apps.cloudConfigHistoryLimit`         | Integer             | yes      | `100`   | `100`                                            | The number of historic values that should be saved in the Cloud Config change history. Valid values: `0`...`Number.MAX_SAFE_INTEGER`.                                                                                                 |
+| `apps.cloudConfigHistoryLimit`         | Integer             | yes      | `100`   | `100`                                            | The number of historic values that should be saved in the Cloud Config change history. Valid values: `0`...`Number.MAX_SAFE_INTEGER`.     
+| `apps.config`                          | Object             | yes      | -        | `{ ... }`                                        | App settings option used to store dashboard configuration on the server.
+| `apps.config.className`                | String             | yes      | _        | `DashboardConfig`                                | The table name used to save and migrate the dashboard configuration. |
 
 ### File
 
@@ -1475,4 +1477,4 @@ As of April 5, 2017, Parse, LLC has transferred this code to the parse-community
 
 [license-svg]: https://img.shields.io/badge/license-BSD-lightgrey.svg
 [license-link]: LICENSE
-[open-collective-link]: https://opencollective.com/parse-server
+[open-collective-link]: https://opencollective.com/parse-server