core: target_temperature_step is broken after 0.96

Home Assistant release with the issue: 0.96.0

Last working Home Assistant release (if known): 0.95

Operating environment (Hass.io/Docker/Windows/etc.): Docker

Component/platform: climate

Description of problem:

    @property
    def target_temperature_step(self):
        """Return the supported step of target temperature."""
        # return self._target_temperature_step
        return 4.0

This code in custom component is not working. Target temperature changes in ui with step 0.5

Problem-relevant configuration.yaml entries and (fill out even if it seems unimportant):

Traceback (if applicable):

Additional information: climate.mqtt component temp_step doesn’t work too