feat(function): add timestamp epoch integer support for to_timezone

[etolbakov]

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Refer to a related PR or issue link

This fixed #3477

What's changed and what's your intention?

updated to_timezone logic to support UNIX millisecond timestamp numerical values like 1711508510000

Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR does not require documentation updates.

[codecov]

Codecov Report

Attention: Patch coverage is 91.30435% with 6 lines in your changes are missing coverage. Please review.

Project coverage is 85.12%. Comparing base (93da45f) to head (ac1e4f3).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3620      +/-   ##
==========================================
- Coverage   85.44%   85.12%   -0.33%     
==========================================
  Files         932      932              
  Lines      155142   155192      +50     
==========================================
- Hits       132567   132102     -465     
- Misses      22575    23090     +515     

[etolbakov]

Hi @tisonkun
Could you please take a look when you have time?

[tisonkun]

Neat and correct. Thank you!

[killme2008]

LGTM