Fix task interference bugs and task repeating

[rtibbles]

• Simplifies how we use task manager to only use single enqueuing of a task, and rely on Kolibri's task requeuing within the life cycle of a task to handle repeat behaviour
• Updates to always use APPEND_OR_REPLACE to ensure that tasks append while running or replace if not running.
• Updates Python for Android to a version on our fork that allow defining a main function in the specified module that will be executed if it exists - it is passed what would normally be passed as the environment variable argument as its sole argument
• This helps prevent the environment variable getting set to the incorrect value when multiple threads are operating (as they do in the work manager context) - this means that job execution will always be passed the proper job_id, and not accidentally read the incorrect job_id from either from an environment variable or a variable set on the __main__ module that is shared across threads.

I tested this with a dummy task defined in the android_app_plugin that used the retry_in method of the job object to repeat itself every 5 seconds. It did this successfully, and also did not interfere or attempt to run other currently active tasks (such as the ping back task or the network connection checking task) which I had seen in previous testing.

Full diff for the change in our P4A fork here: https://github.com/learningequality/python-for-android/compare/4a3c74caf67cad4495f2352ae56ba2b0f1b266c5...5eff8c9f79c8f019073cc7e913219f5ac219ac32

[pcenov]

Hi @rtibbles syncing is working correctly now and the only potential issue that I was able to identify is that the sync status displayed at Coach > Class home > View learners never changes from 'Synced' to 'Not connected to server' (after having force stopped the app) - had to wait for about 20 minutes for it to change to 'Not recently synced or unable to sync'.

There are some errors in the logs such as:

ERROR 2023-11-02 13:17:57,394 kolibri.core.device.soud [user=2389bbe0d3cf341764625349a5c594e8] [server=6a40d55608b125e4a9e45fb854476922] Critical error occurred during syncing: Stage `cleanup` failed
ERROR 2023-11-02 13:17:57,466 kolibri.core.device.soud Stage `cleanup` failed

so adding the logs for you to review as well:

Android device: android.zip ubuntu_server.zip

[rtibbles]

Thanks @pcenov - looking at the logs, I don't think that's the result of this work, but I'll ask around to see!

[rtibbles]

Yes, have filed a follow up on Kolibri: https://github.com/learningequality/kolibri/issues/11485 - so I think this PR is doing what it ought!

[pcenov]

@rtibbles it seems that there's still something wrong with the app though. Now it has stopped syncing (for a brand new learner user) so once again adding the logs.

The server is the same as before:

Android2.zip

ubuntu_server2.zip

[rtibbles]

@pcenov looking at the logs, this seems unrelated to Android specifically, so I have filed the error I saw in the logs as a follow up issue here: https://github.com/learningequality/kolibri/issues/11488