Steps to reproduce:

0/ (Have a moodle in a state where it needs to check for updates - can be done in DB with: UPDATE mdl_config_plugins set value = '1' WHERE name = 'recentfetch' AND plugin = 'core_plugin'
1/ Set your proxy setting to something invalid
2/ Cron cron

Expected Result
---------------
Moodle fails to receive updates but cron continues successfully following that failure

Actual Result:
--------------
Cron aborts with exception:
Outdated or missing info about available updates, forced fetching ... Default exception handler: core_plugin/err_response_http_code Debug: 0

• line 764 of /lib/pluginlib.php: available_update_checker_exception thrown
• line 653 of /lib/pluginlib.php: call to available_update_checker->get_response()
• line 1105 of /lib/pluginlib.php: call to available_update_checker->fetch()
• line 738 of /lib/pluginlib.php: call to available_update_checker->cron_execute()
• line 386 of /lib/cronlib.php: call to available_update_checker->cron()
• line 61 of /admin/cli/cron.php: call to cron_run()

!!! core_plugin/err_response_http_code !!!