executor: fix flashback table faild in uppercase database name (#17093)

[sre-bot]

cherry-pick #17093 to release-3.0

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Signed-off-by: crazycs520 crazycs520@gmail.com

What problem does this PR solve?

Fix below bugs:

drop database if exists Test2;
create database Test2;
use Test2;
create table t (a int);
drop table t;
flashback table t; -- should execute successfully.
(1105, u"Can't find dropped/truncated table: t in DDL history jobs")

drop table t;
drop database if exists Test3;
create database Test3;
use Test3;
create table t (a int);
drop table t;
drop database Test3;
use Test2;
flashback table t; -- should execute successfully.
(1049, u"Unknown database '(Schema ID 62)'")

What is changed and how it works?

No

Related changes

• Need to cherry-pick to the release branch

Check List

Tests

• Unit test
• Manual test (add detailed scripts or steps below)

Side effects

• No

Release note

• Fix flashback table failed in some special cases.

[sre-bot]

/run-all-tests

[zimulala]

@crazycs520
Please fix the conflicts.

[crazycs520]

LGTM

[crazycs520]

/run-all-tests

[crazycs520]

/run-all-tests

[zimulala]

LGTM

[tangenta]

LGTM

[crazycs520]

/run-all-tests