ddl: fix the issue about create columns with wrong default when sql_mode is empty. (#52988)

[ti-chi-bot]

This is an automated cherry-pick of #52988

What problem does this PR solve?

Issue Number: close https://github.com/pingcap/tidb/issues/52972, close https://github.com/pingcap/tidb/issues/51320

Problem Summary: Case1:

set @@sql_mode='STRICT_TRANS_TABLES';
drop table if exists t1;
create table t1(a int);
insert into t1 values(1);
alter table t1 add column(b tinyint default '11111111');

Case2:

set @@sql_mode='';
drop table if exists t1;
create table t1(a int);
insert into t1 values(1);
alter table t1 add column(b tinyint default '11111111');

Now the TiDB behaviors:

• When the @@sql_mode is STRICT_TRANS_TABLES(Case1) the result is Invalid default value for 'b'.
• When the @@sql_mode is ''(Case2) the result is successful.

Now the MySQL(MySQL 5.7.44 and 8.0.18 MySQL) behaviors:

• In Both cases the result is Invalid default value for 'b'.

What changed and how does it work?

Check List

Tests

• [x] 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

[ti-chi-bot[bot]]

[APPROVALNOTIFIER] This PR is APPROVED

This pull-request has been approved by: Defined2014, tangenta

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Needs approval from an approver in each of these files: - ~~[OWNERS](https://github.com/pingcap/tidb/blob/release-8.1/OWNERS)~~ [Defined2014,tangenta] - ~~[pkg/ddl/OWNERS](https://github.com/pingcap/tidb/blob/release-8.1/pkg/ddl/OWNERS)~~ [tangenta] 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[bot]]

[LGTM Timeline notifier]

Timeline:

• 2024-04-30 07:44:16.343853313 +0000 UTC m=+343210.100988886: :ballot_box_with_check: agreed by Defined2014.
• 2024-04-30 07:52:12.684475919 +0000 UTC m=+343686.441611490: :ballot_box_with_check: agreed by tangenta.