added built-in timestamp transformation in the date function

[ghost]

What type of PR is this?

• bug
• feature
• enhancement

What problem(s) does this PR solve?

Issue(s) number: #2747

Description:

Added the possibility of converting stored timestamps (int) into a convenient readable date string.
Integrated into a stock date() function. This will save the user from the need for additional transformations.

How do you solve it?

Added the detection of a stored/requested type. If the date(int) function is called, the date string desired to the user is returned. There was a refusal earlier.

Special notes for your reviewer, ex. impact of this fix, design document, etc:

Before:

After:

Unit Test:

Checklist:

Tests:

• Unit test(positive and negative cases)
• Function test
• Performance test
• N/A

Affects:

• Documentation affected (Please add the label if documentation needs to be modified.)
• Incompatibility (If it breaks the compatibility, please describe it and add the label.）
• If it's needed to cherry-pick (If cherry-pick to some branches is required, please label the destination version(s).)
• Performance impacted: Consumes more CPU/Memory

Release notes:

added built-in timestamp transformation in the date function

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