mpp: Fix the crash or error when mpp generate empty task list. (#31658)

[ti-srebot]

cherry-pick #31658 to release-5.1
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---

What problem does this PR solve?

Issue Number: close #31636

Problem Summary: apply may generate an empty range list, and then generate an empty mpp task list, but we don't handle it correctly.

What is changed and how it works?

handle the situation when mpp task list is empty.

Check List

Tests

• Unit test
• Integration test
  need add the original case to our intergration cases

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

Fix the crash or error when generating an empty mpp task list.

[ti-chi-bot]

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[ti-chi-bot]

@ti-srebot: This cherry pick PR is for a release branch and has not yet been approved by release team.
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[ti-srebot]

/run-all-tests

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[VelocityLight]

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