Switch mirror from Scenario Outline to Scenarios

Hilariously the Scenario Outline approach worked perfectly for Smokey, but it
doesn't seem to be supported by either the json formatter for cucumber (which
only shows one test result in the outline), nor the nagios_check_cache.py
script.

By changing these checks back to 4 individual scenarios, I should be able to
re-enable smokey checks in Nagios/Icinga without rewriting the formatter or
the cache checker just for this one check.