Revert "Add mg/m³ as a valid UOM for sensor/number Carbon Monoxide device class" (#153196)

tests/util/test_unit_conversion.py

@@ -44,7 +44,6 @@ from homeassistant.util.unit_conversion import (
     AreaConverter,
     BaseUnitConverter,
     BloodGlucoseConcentrationConverter,
-    CarbonMonoxideConcentrationConverter,
     ConductivityConverter,
     DataRateConverter,
     DistanceConverter,
@@ -79,7 +78,6 @@ _ALL_CONVERTERS: dict[type[BaseUnitConverter], list[str | None]] = {
         AreaConverter,
         BloodGlucoseConcentrationConverter,
         MassVolumeConcentrationConverter,
-        CarbonMonoxideConcentrationConverter,
         ConductivityConverter,
         DataRateConverter,
         DistanceConverter,
@@ -116,11 +114,6 @@ _GET_UNIT_RATIO: dict[type[BaseUnitConverter], tuple[str | None, str | None, flo
         UnitOfBloodGlucoseConcentration.MILLIMOLE_PER_LITER,
         18,
     ),
-    CarbonMonoxideConcentrationConverter: (
-        CONCENTRATION_MILLIGRAMS_PER_CUBIC_METER,
-        CONCENTRATION_PARTS_PER_MILLION,
-        1.145609,
-    ),
     ConductivityConverter: (
         UnitOfConductivity.MICROSIEMENS_PER_CM,
         UnitOfConductivity.MILLISIEMENS_PER_CM,
@@ -287,20 +280,6 @@ _CONVERTED_VALUE: dict[
             UnitOfBloodGlucoseConcentration.MILLIGRAMS_PER_DECILITER,
         ),
     ],
-    CarbonMonoxideConcentrationConverter: [
-        (
-            1,
-            CONCENTRATION_PARTS_PER_MILLION,
-            1.145609,
-            CONCENTRATION_MILLIGRAMS_PER_CUBIC_METER,
-        ),
-        (
-            120,
-            CONCENTRATION_MILLIGRAMS_PER_CUBIC_METER,
-            104.74778,
-            CONCENTRATION_PARTS_PER_MILLION,
-        ),
-    ],
     ConductivityConverter: [
         # Deprecated to deprecated
         (5, UnitOfConductivity.SIEMENS, 5e3, UnitOfConductivity.MILLISIEMENS),