feat: physical optimizer RemoveDuplicate to remove duplicate exec plans

[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?

A tiny physical rule to remove useless adjoining plans.

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

All modified and coverable lines are covered by tests ✅

Project coverage is 85.33%. Comparing base (336db38) to head (075e667).
Report is 1 commits behind head on main.

❗ Current head 075e667 differs from pull request most recent head a7d703f. Consider uploading reports for the commit a7d703f to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3839      +/-   ##
==========================================
- Coverage   85.78%   85.33%   -0.46%     
==========================================
  Files         950      955       +5     
  Lines      162714   163135     +421     
==========================================
- Hits       139582   139205     -377     
- Misses      23132    23930     +798     

[killme2008]

LGTM. But I have a few questions, may you take a look? Thank you.