planner: fix panic during starting tidb-server if creating global binding for partition table (#40402)

[ti-chi-bot]

This is an automated cherry-pick of #40402

What problem does this PR solve?

Issue Number: close #40368

Problem Summary:

What is changed and how it works?

fix panic during starting tidb-server if creating global binding for partition table

Check List

Tests

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

create table t1(a int, b int, key (a)) partition by range (a) (partition p0 values less than (10), partition p1 values less than (20));
create global binding for select * from t1 using select * from t1 use index (a);
show global bindings;

restart the tidb-server and make sure it restart successfully

Release note

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

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• hawkingrei
• xuyifangreeneyes

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[Yisaer]

/retest-required

[Yisaer]

/merge

[ti-chi-bot]

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

Commit hash: 5080874