Comment 4 for bug 1976169

Reviewed: https://review.opendev.org/c/openstack/charm-octavia-diskimage-retrofit/+/848007
Committed: https://opendev.org/openstack/charm-octavia-diskimage-retrofit/commit/aa37294b0f3156767475676241738489d2e296d9
Submitter: "Zuul (22348)"
Branch: stable/yoga

commit aa37294b0f3156767475676241738489d2e296d9
Author: Mustafa Kemal Gilor <email address hidden>
Date: Thu Jun 23 16:13:22 2022 +0300

    invoke `hookenv._run_atexit()` when action ends

    the registered callbacks for `atexit()` were not executing due to
    `_run_atexit()` is not being called, the `ch_core.hookenv._run_atexit()`
    function is now explicitly called when action ends. also moved
    `ch_core.hookenv._run_atstart()` call to `main()` for consistency.

    Closes-bug: #1976169

    Signed-off-by: Mustafa Kemal Gilor <email address hidden>
    Change-Id: I2b976af908dd6ae6248f405fa6980beef0554be5
    (cherry picked from commit 7e80dce5d35e93ece18220978073c9f1193fd473)