feat: implement Display for PartitionExpr

[Kelvinyu1117]

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This closes #3985 .

What's changed and what's your intention?

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Please explain IN DETAIL what the changes are in this PR and why they are needed:

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Checklist

• I have written the necessary rustdoc comments.
• I have added the necessary unit tests and integration tests.
• This PR requires documentation updates.

[tisonkun]

Although I have a suggestion to write the test in a more tidy way:

let cases = [
  (Operand::Column(..), RestrictedOp::.., Operand::Column(..), "a = b"),
  ...
]

or even pack the input and output into a temporary struct,

This patch itself is good to merge.

Thanks for your contribution!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 85.19%. Comparing base (c2218f8) to head (38f9856).

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #4087      +/-   ##
==========================================
- Coverage   85.49%   85.19%   -0.30%     
==========================================
  Files         991      991              
  Lines      172968   173053      +85     
==========================================
- Hits       147878   147437     -441     
- Misses      25090    25616     +526     

[Kelvinyu1117]

Although I have a suggestion to write the test in a more tidy way:

let cases = [
  (Operand::Column(..), RestrictedOp::.., Operand::Column(..), "a = b"),
  ...
]

or even pack the input and output into a temporary struct,

This patch itself is good to merge.

Thanks for your contribution!

Thanks, updated.

[killme2008]

LGTM. Thank you.