docs: Use UI test screenshots in docs

Signed-off-by: mahendrapaipuri <[email protected]>

docs/jupyterlab-extension.md

@@ -11,21 +11,24 @@ notebooks as they launch a regular notebook from JupyterLab launcher.
 After installing Jupytext extension, users will have a new category in the launcher
 called Jupytext as shown below:
 
-![](images/jupyterlab_launcher.png)
+![](../jupyterlab/packages/jupyterlab-jupytext-extension/ui-tests/tests/jupytext-launcher.spec.ts-snapshots/launcher-category-jupytext-linux.png)
 
 Users can remove and/or add new formats to the Jupytext section _via_ `Settings>Jupytext`.
 
-![](images/jupyterlab_settings.png)
+![](../jupyterlab/packages/jupyterlab-jupytext-extension/ui-tests/tests/jupytext-settings.spec.ts-snapshots/jupytext-settings-panel-jupytext-linux.png)
 
-By clicking `Add` and adding a new format, say `qmd`, will
-add the Quatro Text Notebook to the launcher. **Note** that users need to refresh the current browser tab when they modify the settings for them to take effect.
-
-Besides, users can also change the category of Text Notebook launcher icons using
-`Category` field in the Settings. For example, by using `Notebook` as category, all
-Text Notebook launchers will be moved into `Notebook` category.
+By (un)selecting different formats, users can filter the items in launcher and main menu. **Note** that users need to refresh the current browser tab when they modify the settings for them to take effect.
 
 ## Main menu
 
-It is also possible to launch text notebooks and/or pair existing notebooks from the dedicated Jupytext main menu as shown below.
+It is also possible to create new text notebooks and/or pair existing notebooks from main menu and dedicated Jupytext main menu, respectively.
+
+Following screenshot shows the `New Text Notebook` submenu available in `File` menu.
+
+![](../jupyterlab/packages/jupyterlab-jupytext-extension/ui-tests/tests/jupytext-menu.spec.ts-snapshots/opened-jupytext-menu-file-new-text-notebook-jupytext-linux.png)
+
+Similarly, to pair existing notebooks, users can go to `Jupytext` menu on main menu as shown below:
+
+![](../jupyterlab/packages/jupyterlab-jupytext-extension/ui-tests/tests/jupytext-menu.spec.ts-snapshots/opened-jupytext-menu-jupytext-pair-notebook-jupytext-linux.png)
 
-![](images/jupyterlab_main_menu.png)
+All the options are greyed out in the above screenshot as there is no notebook widget currently active. Once the user opens a new notebook, the options will become available.