table, parser: check for invalid GBK characters before insertion

[tangenta]

What problem does this PR solve?

Issue Number: close #28778.

Problem Summary:

À is not a valid GBK character, TiDB should report an "incorrect string value" error.

mysql> create table t (a varchar(255) charset gbk);
Query OK, 0 rows affected (0.04 sec)
mysql> insert into t values ('À');
Query OK, 1 row affected

What is changed and how it works?

Add IsValid function for Encoding.

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

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• xiongjiwei
• zimulala

To complete the pull request process, please ask the reviewers in the list to review by filling /cc @reviewer in the comment.
After your PR has acquired the required number of LGTMs, you can assign this pull request to the committer in the list by filling /assign @committer in the comment to help you merge this pull request.

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

Reviewer can indicate their review by submitting an approval review.
Reviewer can cancel approval by submitting a request changes review.

[xiongjiwei]

/lgtm cancel

[zimulala]

@tangenta Is this ready to review?

[tangenta]

Blocked by #29736.

[zimulala]

LGTM

[xiongjiwei]

/merge

[ti-chi-bot]

This pull request has been accepted and is ready to merge.

Commit hash: 74f1b49

[xiongjiwei]

/hold

[xiongjiwei]

/hold

test is failed

[tangenta]

@xiongjiwei The test is confirmed to be unstable.

/unhold

[tangenta]

/merge