add default color variable for alerting device_classes

[Mariusthvdb]

now we have:

      --state-binary_sensor-carbon_monoxide-on-color: var(--red-color);
      --state-binary_sensor-gas-on-color: var(--red-color);
      --state-binary_sensor-heat-on-color: var(--red-color);
      --state-binary_sensor-lock-on-color: var(--red-color);
      --state-binary_sensor-moisture-on-color: var(--red-color);
      --state-binary_sensor-problem-on-color: var(--red-color);
      --state-binary_sensor-safety-on-color: var(--red-color);
      --state-binary_sensor-smoke-on-color: var(--red-color);
      --state-binary_sensor-sound-on-color: var(--red-color);
      --state-binary_sensor-tamper-on-color: var(--red-color);

to set colors on those individual device-classes, we have no default fallback color anymore, besides the HA listed above.

It would be really nice to have a

state-binary_sensor-alerting-color: var(--red-color);

as a fallback option for those, and be able to set that in themes like:

state-binary_sensor-alerting-color: var(--alert-color)

or, if that would be a better name:

state-binary_sensor-alert-on-color: var(--alert-color) 

there was some discussion in this in the community https://community.home-assistant.io/t/2022-12-color-states-are-broken-unusable/499890/784.

thanks for considering