Put a semi-colon ; on it’s own line at the end of your configuration.yaml file and use the CLI to restart the host machine:
ha ho reboot
The semi-colon will cause your home assistant to fail the configuration check when it attempts to start and will stop the boot-looping. Hopefully the reboot will stop the running task that is preventing your use of the supervisor.
Use the console to update to 2021.9.1
ha core update --version 2021.9.1
Remove the semi-colon from your configuration file and restart.
I have tried twice to upgrade to 2021.9.1 then 2021.9.2 using the following commands. sudo su -s /bin/bash homeassistant, source /srv/homeassistant/bin/activate, pip3 install --upgrade homeassistant. All of the outputs say the installation completed but when I try to connect with the browser (http://192.168.1.17:8123/lovelace-yaml/default_view) I never connect. When I reinstall 2021.8.8 with pip3 install homeassistant==2021.8.8 every thing works. Any help would be appreciated.