Make cloud switch entity _update_state function a coro

[jpbede]

Description

Make the _update_state function of the cloud switch entities a coro.

Motivation and Context

The async_listen_updates of the cloud client requires the function to be a coro, as the function uses the async_create_catching_coro logging helper of core, which (in some nested functions) always awaits.

How has this been tested?

This appeared while beta testing home-assistant/core#111797.
I applied this change on my prod system and the log went away.

Screenshots (if appropriate):

Types of changes

• Bug fix (non-breaking change which fixes an issue)
• New feature (non-breaking change which adds functionality)
• Breaking change (fix or feature that would cause existing functionality to not work as expected)
• Other

Checklist

• My code follows the code style of this project.
• My change requires a change to the documentation.
• I have updated the documentation accordingly.

[sonarcloud]

Quality Gate passed

Issues
0 New issues
0 Accepted issues

Measures
0 Security Hotspots
No data about Coverage
0.0% Duplication on New Code

See analysis details on SonarCloud

[frenck]

Thanks, @jpbede 👍

../Frenck