Check api - should not report errors/warnings if the plugin is disabled

[keevan]

Use case: dataflows might be failing on that particular environment and deemed OK to disable until fixed or needed

Currently, all bad dataflows need to be adjusted to become green (generally good), but if they cannot due to external factors (e.g. integration doesn't flow on that environment), then you are stuck with disabling the dataflow or changing it to check the external dependency and finish without errors (which might not be correct).

A quicker approach which seems reasonable, would be to disable the checks if the plugin itself is disabled, which would result in the same state, if all the individual dataflows were disabled.