modernize thermostat auto and heat/cool icon

[raythefourth]

Description

Change thermostat auto icon from mdi:calendar-sync to mdi:thermostat-auto and heat_cool icon from mdi:autorenew to mdi:sun-snowflake-variant.

Related Issue

This PR fixes or closes issue: fixes #1712

Motivation and Context

The new icon is more appropriate.

How Has This Been Tested

The icon is available since July 5 2022.

Types of changes

• 🐛 Bug fix (non-breaking change which fixes an issue)
• 🚀 New feature (non-breaking change which adds functionality)
• 🌎 Translation (addition or update a translation)
• ⚙️ Tech (code style improvement, performance improvement or dependencies bump)
• 📚 Documentation (fix or addition in the documentation)
• ⚠️ Breaking change (fix or feature that would cause existing functionality to change)

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.
• I have tested the change locally.
• I followed the steps if I add a new language .

[piitaya]

Thank you for the fix. Can you also change the heat_cool icon to mdi:sun-snowflake-variant so we have the same icons as Home Assistant front-end.

[piitaya]

Thank you !