add test case for pk string MinMax check_equal

[hehechen]

What problem does this PR solve?

#3347

What is changed and how it works?

add test case for pk string MinMax check_equal

Tests

• Unit test

Release note

None

[ti-chi-bot]

[REVIEW NOTIFICATION]

This pull request has been approved by:

• JaySon-Huang

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[JaySon-Huang]

We never use DataTypeArray in TiFlash, why do we need to add tests for it?

[JaySon-Huang]

/merge

[ti-chi-bot]

@JaySon-Huang: It seems you want to merge this PR, I will help you trigger all the tests:

/run-all-tests

You only need to trigger /merge once, and if the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

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[ti-chi-bot]

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

Commit hash: 3d5cde0

[ti-chi-bot]

@hehechen: Your PR was out of date, I have automatically updated it for you.

At the same time I will also trigger all tests for you:

/run-all-tests

If the CI test fails, you just re-trigger the test that failed and the bot will merge the PR for you after the CI passes.

Instructions for interacting with me using PR comments are available here. If you have questions or suggestions related to my behavior, please file an issue against the ti-community-infra/tichi repository.

[sre-bot]

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