feat(android): ota: Add python dependency for update-engine

Add step to install the google module required to run the
"gen_update_config.py" command.

Signed-off-by: Maxime Fournier <[email protected]>
[mkorpershoek: reworded msg a bit]
Signed-off-by: Mattijs Korpershoek <[email protected]>

Author: FournierMx

source/android/Foundational_Components_OTA.rst

@@ -58,6 +58,12 @@ OTA via ``adb sideload``
 OTA via Update Engine
 *********************
 
+   #. Install the python dependency for the google module
+
+      .. code-block:: console
+
+         $ pip install --user google-api-python-client
+
    #. Build the OTA package
 
       .. code-block:: console