* prometheus-nginx-exporter: 0.5.0 -> 0.6.0
* nixos/prometheus-nginx-exporter: update for 0.6.0
Added new option constLabels and updated virtualHost name in the
exporter's test.
We don't want to ignore config that can mess up machines. In general
this should always fail evaluation, as you think you are changing
behaviour and don't, which can easily create run-time errors we can
catch early.
- prometheus exporters are now configured with
`services.prometheus.exporters.<name>`
- the exporters are now defined by attribute sets
from which the options for each exporter are generated
- most of the exporter definitions are used unchanged,
except for some changes that should't have any impact
on the functionality.