unit tests coverage is very limited

[Tianqi Xiao]

The unit tests have a lot of room for improvements. The current overall coverage is very low (41%). Some key scripts, including actions.py and openstack_service_checks.py, don't even have any unit tests.

---------- coverage: platform linux, python 3.8.10-final-0 -----------
Name Stmts Miss Cover
----------------------------------------------------------------------
actions/actions.py 36 36 0%
files/plugins/check_cinder_services.py 54 12 78%
files/plugins/check_contrail_analytics_alarms.py 86 41 52%
files/plugins/check_masakari.py 44 17 61%
files/plugins/check_nova_services.py 79 29 63%
files/plugins/check_octavia.py 135 25 81%
files/plugins/check_port_security.py 139 90 35%
files/run_allocation_checks.py 110 20 82%
files/run_rally.py 61 61 0%
lib/lib_openstack_service_checks.py 502 333 34%
reactive/openstack_service_checks.py 162 162 0%
----------------------------------------------------------------------
TOTAL 1408 826 41%

[Eric Chen (eric-chen)]

Migrate to https://github.com/canonical/charm-openstack-service-checks/issues