* Enhance charm's life cycle.

* Remove unused property.

* Cherry-pick from 7513f18, and fix
linting.

Co-authored-by: jneo8 <[email protected]>

Continue to remove refactoring code from the previous branch, and fix
status handling.

* Move "exporter health check failed and restart" logic into charm.py

* add resource check in update_status event, and change Error -> Blocked

* Fix typo

* Add unittests.

* Update unit test docstring and name.

* - Used `parameterized`
- Fixed some warning message in unittest
- Patched exporter retry constants

* Separate enabling logic of individual ipmi services monitoring

* Add and refactor unit tests

* fix: lifecycle bug fix

- Remove install retry
- Add cache to hw_white_list to avoid repeat calls
- Fix missing resource failed msg in update status hook

* fix: Remove resource_failed_msg

* fix: Fix type checking comments and defer relation_join hook if checking not pass

* fix: Missing return after grafana-agent relation join event defer

* fix: Skip removing pkg on IPMI strategy

Skip removing package because we afraid this cause
dependency error for any other services on the same machine.

* fix: Skip remove ssacli pkg and repo

Fix failure functional test caused because of life-cycle changing.

* fix: apt install freeipmi-tools failed on focal

Fix: #128