expression: remove old regexpBaseFuncSig and rename regexpNewBaseFuncSig to regexpBaseFuncSig

[lcwangchao]

What problem does this PR solve?

Issue Number: close #49684

Problem Summary:

After #49584 and #49642 the old regexpBaseFuncSig is useless. Now, we can remove it and rename regexpNewBaseFuncSig to regexpBaseFuncSig now.

What changed and how does it work?

remove old regexpBaseFuncSig and rename regexpNewBaseFuncSig to regexpBaseFuncSig

Check List

Tests

• Unit test
• Integration test
• Manual test (add detailed scripts or steps below)
• No need to test

  • I checked and no code files have been changed.

Side effects

• Performance regression: Consumes more CPU
• Performance regression: Consumes more Memory
• Breaking backward compatibility

Documentation

• Affects user behaviors
• Contains syntax changes
• Contains variable changes
• Contains experimental features
• Changes MySQL compatibility

Release note

Please refer to Release Notes Language Style Guide to write a quality release note.

None

[codecov]

Codecov Report

Merging #49685 (fc33f6a) into master (b1e5d61) will increase coverage by 0.4387%.
Report is 2 commits behind head on master.
The diff coverage is 76.1904%.

Additional details and impacted files

@@               Coverage Diff                @@
##             master     #49685        +/-   ##
================================================
+ Coverage   70.9732%   71.4120%   +0.4387%     
================================================
  Files          1368       1424        +56     
  Lines        398095     415762     +17667     
================================================
+ Hits         282541     296904     +14363     
- Misses        95813     100067      +4254     
+ Partials      19741      18791       -950     

Flag	Coverage Δ
integration	43.6916% <76.1904%> (?)
unit	70.9733% <100.0000%> (+<0.0001%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Components	Coverage Δ
dumpling	53.9663% <ø> (ø)
parser	∅ <ø> (∅)
br	47.3069% <ø> (-5.5971%)	⬇️

[hawkingrei]

/retest

[xzhangxian1008]

LGTM

[ti-chi-bot]

@xzhangxian1008: adding LGTM is restricted to approvers and reviewers in OWNERS files.

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LGTM

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[windtalker]

LGTM

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: windtalker, xzhangxian1008, YangKeao

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[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-12-22 03:48:42.187259227 +0000 UTC m=+1192013.224486156: ☑️ agreed by YangKeao.
• 2023-12-22 04:52:42.085055044 +0000 UTC m=+1195853.122281956: ☑️ agreed by windtalker.