Is your feature request related to a problem or challenge?

The now() function currently is hardcoded to use +00:00 timezone. Now that functions have access to the ConfigOptions now() can be updated to use the tz set in 'datafusion.execution.time_zone'

Describe the solution you'd like

now() returns a timestamp in the tz set via the 'datafusion.execution.time_zone' config option.

Describe alternatives you've considered

Leave unchanged.

Additional context

No response