Callback before_footer in block_powerbi component should be migrated to new hook callback

Description: Debugging message when loading site after install. This is causing unit test errors in Moodle 4.4+

Callback before_footer in block_powerbi component should be migrated to new hook callback for core\hook\output\before_footer_html_generation

    line 7481 of /lib/moodlelib.php: call to debugging()
    line 7545 of /lib/moodlelib.php: call to {closure}()
    line 71 of /lib/classes/hook/output/before_footer_html_generation.php: call to get_plugins_with_function()
    line 1505 of /lib/outputrenderers.php: call to core\hook\output\before_footer_html_generation->process_legacy_callbacks()
    line 192 of /my/index.php: call to core_renderer->footer()