feat: support generate_series with timestamptz type

[chenzl25]

Is your feature request related to a problem? Please describe.

RisingWave supports

select * from generate_series('2025-01-01'::timestamp, '2025-01-02'::timestamp, interval '1 hour');

However it doesn't support

select * from generate_series('2025-01-01'::timestamptz, '2025-01-02'::timestamptz, interval '1 hour');

Describe the solution you'd like

No response

Describe alternatives you've considered

No response

Additional context

No response