Fix datetime parameter validation for list events

[piitaya]

Proposed change

Fix datetime parameter validation for list events. I also fixed the demo calendar integration to use the server timezone

Type of change

• Dependency upgrade
• Bugfix (non-breaking change which fixes an issue)
• New integration (thank you!)
• New feature (which adds functionality to an existing integration)
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• Breaking change (fix/feature causing existing functionality to break)
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Additional information

• This PR fixes or closes issue: fixes Can not use start_date_time and end_date_time in list events calendar service #95751
• This PR is related to issue:
• Link to documentation pull request:

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[home-assistant]

Hey there @home-assistant/core, mind taking a look at this pull request as it has been labeled with an integration (calendar) you are listed as a code owner for? Thanks!

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[home-assistant]

Hey there @home-assistant/core, mind taking a look at this pull request as it has been labeled with an integration (demo) you are listed as a code owner for? Thanks!

Code owner commands

Code owners of demo can trigger bot actions by commenting:

• @home-assistant close Closes the pull request.
• @home-assistant rename Awesome new title Renames the pull request.
• @home-assistant reopen Reopen the pull request.
• @home-assistant unassign demo Removes the current integration label and assignees on the pull request, add the integration domain after the command.

[allenporter]

This is a bug in list_events so we can move the logic into list_events similar to the other caller

core/homeassistant/components/calendar/__init__.py

Line 581 in 4581c36

calendar_event_list = await entity.async_get_events(

and it should call dt_util.as_local

[allenporter]

Sent #95804 to fix the list events bug