parser: reset lexer.identifierDot correctly when reusing parsers (#45903)

[ti-chi-bot]

This is an automated cherry-pick of #45903

What problem does this PR solve?

Issue Number: close #45898

Problem Summary: parser: reset lexer.identifierDot correctly when reusing parsers

What is changed and how it works?

parser: reset lexer.identifierDot correctly when reusing parsers

Check List

Tests

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

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

[ti-chi-bot]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: hawkingrei, tiancaiamao

The full list of commands accepted by this bot can be found here.

The pull request process is described here

Needs approval from an approver in each of these files:

• OWNERS [hawkingrei,tiancaiamao]

Approvers can indicate their approval by writing /approve in a comment
Approvers can cancel approval by writing /approve cancel in a comment

[ti-chi-bot]

[LGTM Timeline notifier]

Timeline:

• 2023-08-08 09:21:34.349019691 +0000 UTC m=+18058.898035675: ☑️ agreed by hawkingrei.
• 2023-08-08 09:26:58.099621898 +0000 UTC m=+18382.648637885: ☑️ agreed by tiancaiamao.

[hawkingrei]

/retest

[qw4990]

/retest-required

[hawkingrei]

/retest

[hawkingrei]

/retest

[Ivy-YinSu]

/retest-required

[qw4990]

/retest-required

[codecov]

Codecov Report

❗ No coverage uploaded for pull request base (release-6.5@74abc22). Click here to learn what that means.
The diff coverage is n/a.

Additional details and impacted files

@@               Coverage Diff                @@
##             release-6.5     #45909   +/-   ##
================================================
  Coverage               ?   73.7499%           
================================================
  Files                  ?       1084           
  Lines                  ?     348365           
  Branches               ?          0           
================================================
  Hits                   ?     256919           
  Misses                 ?      75009           
  Partials               ?      16437           

[Ivy-YinSu]

/test unit-test

[tiprow]

@Ivy-YinSu: No presubmit jobs available for pingcap/tidb@release-6.5

In response to this:

/test unit-test

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the kubernetes/test-infra repository.