Query with `Apply` executor may throw `query set must not be null when register task` error

[windtalker]

Bug Report

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1. Minimal reproduce step (Required)

For query that contains Apply executor, and if the apply need to run mpp query, the query may throw error, a typical error is

[2023/06/21 07:02:33.165 +00:00] [ERROR] [local_mpp_coordinator.go:372] ["mpp dispatch response meet error"] [error="DB::Exception: Check query_set != nullptr failed: query set must not be null when register task"] [timestamp=442323682909224968] [task=796] [task-mpp-version=1] [error-mpp-version=0]

Introduced by #7644

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3. What did you see instead (Required)

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