feat: clamp function

[waynexia]

I hereby agree to the terms of the GreptimeDB CLA.

Refer to a related PR or issue link (optional)

What's changed and what's your intention?

Implement the CLAMP(val, min, max) that can clamp the given value into the range [min, max].

Similar function in other systems:

• Prometheu
• PostgreSQL

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 85.62874% with 48 lines in your changes are missing coverage. Please review.

Project coverage is 85.06%. Comparing base (3f3ef2e) to head (8fa3529).
Report is 2 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3465      +/-   ##
==========================================
- Coverage   85.41%   85.06%   -0.35%     
==========================================
  Files         896      897       +1     
  Lines      147185   147851     +666     
==========================================
+ Hits       125711   125776      +65     
- Misses      21474    22075     +601     

[etolbakov]

LGTM

[Taylor-lagrange]

LGMT