types: Fix "Invalid time format" caused by daily saving time (#13614)

[sre-bot]

cherry-pick #13614 to release-2.1

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What problem does this PR solve?

Fix #13605

What is changed and how it works?

Some regions use daylight saving time.

In MySQL, it will throw the error "Invalid time format" when use the datetime between the advanced hour of daylight saving time (e.g. 2018/3/11 2:00~3:00 in Los Angeles). Actually, if the @@time_zone sql variable is set to region where uses daylight saving time, the error occurred. But if the @@time_zone is other region, no error occurred, even if the system time zone is the region where uses daylight saving time.

But TiDB will throw an unexpected error "Invalid time format" when the timezone of system is in region where use daylight saving time.

Fix method:

When checking the time, we use the SQL variable @@time_zone instead of directly use the timezone of system.

In details, In checkTimestampType function, we use the TimeZone of statementContext, instead of local timezone provided by Golang.

Check List

Tests

• Unit test

Code changes

• None

Side effects

• None

Related changes

• None

Release note

• None

[sre-bot]

/run-all-tests

[Deardrops]

/run-all-tests

[bb7133]

LGTM

[Deardrops]

/run-all-tests

[bb7133]

/run-unit-test

[Deardrops]

/run-unit-test

[Deardrops]

/run-unit-test

[AilinKid]

LGTM