parser: remove 'stats_extended' from the reserved keywords

[bb7133]

What problem does this PR solve?

Issue Number: clos #39573

Problem Summary:

This is an example: as stated in the title.

What changed and how does it work?

This is an example: as stated in the title.

Check List

Tests

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

  • [ ] I checked and no code files have been changed.

Side effects

• NA

Documentation

• NA

Release note

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

Remove 'stats_extended' from the reserved keywords

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is NOT APPROVED

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[ti-chi-bot[bot]]

@bb7133: The following tests failed, say /retest to rerun all failed tests or /retest-required to rerun all mandatory failed tests:

Test name	Commit	Details	Required	Rerun command
idc-jenkins-ci-tidb/unit-test	7dbec1a99b8fd6d99c03fe41f7cbae1f1f391bc0	link	true	/test unit-test
idc-jenkins-ci-tidb/check_dev	7dbec1a99b8fd6d99c03fe41f7cbae1f1f391bc0	link	true	/test check-dev

Full PR test history. Your PR dashboard.

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[ti-chi-bot[bot]]

[FORMAT CHECKER NOTIFICATION]

Notice: To remove the do-not-merge/needs-linked-issue label, please provide the linked issue number on one line in the PR body, for example: Issue Number: close #123 or Issue Number: ref #456.

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[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 55.0199%. Comparing base (1d698c7) to head (7dbec1a). Report is 16 commits behind head on master.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## master #53014 +/- ## ================================================= - Coverage 72.3811% 55.0199% -17.3612% ================================================= Files 1482 1613 +131 Lines 428743 605400 +176657 ================================================= + Hits 310329 333091 +22762 - Misses 99115 249062 +149947 - Partials 19299 23247 +3948 ``` | [Flag](https://app.codecov.io/gh/pingcap/tidb/pull/53014/flags?src=pr&el=flags&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | Coverage Δ | | |---|---|---| | [integration](https://app.codecov.io/gh/pingcap/tidb/pull/53014/flags?src=pr&el=flag&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `22.9375% <ø> (?)` | | Flags with carried forward coverage won't be shown. [Click here](https://docs.codecov.io/docs/carryforward-flags?utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap#carryforward-flags-in-the-pull-request-comment) to find out more. | [Components](https://app.codecov.io/gh/pingcap/tidb/pull/53014/components?src=pr&el=components&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | Coverage Δ | | |---|---|---| | [dumpling](https://app.codecov.io/gh/pingcap/tidb/pull/53014/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `53.9957% <ø> (ø)` | | | [parser](https://app.codecov.io/gh/pingcap/tidb/pull/53014/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `∅ <ø> (∅)` | | | [br](https://app.codecov.io/gh/pingcap/tidb/pull/53014/components?src=pr&el=component&utm_medium=referral&utm_source=github&utm_content=comment&utm_campaign=pr+comments&utm_term=pingcap) | `44.5173% <ø> (+3.3734%)` | :arrow_up: |