[fix](planner) fix orthogonal_bitmap_union_count planner : wrong PREAGGREGATION

[lihuigang]

Proposed changes

Problem summary

Execution plan display when using orthogonal_bitmap_union_count function:

PREAGGREGATION: OFF

Reason: Invalid Aggregate Operator: orthogonal_bitmap_union_count

The correct plan is: PREAGGREGATION: ON

Checklist(Required)

1. Does it affect the original behavior:
   • Yes
   • No
   • I don't know
2. Has unit tests been added:
   • Yes
   • No
   • No Need
3. Has document been added or modified:
   • Yes
   • No
   • No Need
4. Does it need to update dependencies:
   • Yes
   • No
5. Are there any changes that cannot be rolled back:
   • Yes (If Yes, please explain WHY)
   • No

Further comments

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